Chapter LI: Bella (48)

Defn: Chalcedony in parallel layers of different shades of color. It is used for making cameos, the figure being cut in one layer with the next as a ground. Onyx marble, a banded variety of marble or calcium carbonate resembling onyx. It is obtained from Mexico.

OO Oo, a.

Defn: One. [Obs.] Chaucer.

OO O"ö, n. Etym: [Hawaiian.] (Zoöl.)

Defn: A beautiful bird (Moho nobilis) of the Hawaiian Islands. It yields the brilliant yellow feathers formerly used in making the royal robes. Called also yellow-tufted honeysucker.

OOECIUM O*oe"ci*um, n.; pl. Ooecia. Etym: [NL., fr. Gr. (Zoöl.)

Defn: One of the special zooids, or cells, of Bryozoa, destined to receive and develop ova; an ovicell. See Bryozoa.

OOGENESIS; OOEGENESIS O`ö*gen"e*sis, n. Etym: [Gr. genesis.] (Physiol.)

Defn: The development, or mode of origin, of the ova.

OOGONIUM; OOEGONIUM O`ö*go"ni*um, n.; pl. L. Oögonia, E. Oögoniums. Etym: [NL., fr. Gr. (Bot.)

Defn: A special cell in certain cryptogamous plants containing oöspheres, as in the rockweeds (Fucus), and the orders Vaucherieæ and Peronosporeæ.

OOIDAL O*oi"dal, a. Etym: [Gr. (Biol.)

Defn: Shaped like an egg.

OOK Ook, n.

Defn: Oak. [Obs.] "A branched ook." Chaucer.

OOLITE; OOELITE O"ö*lite, n. Etym: [Gr. -lite: cf.F. oölithe. So named from its resemblance to the roe of fish.] (Geol.)

Defn: A variety of limestone, consisting of small round grains, resembling the roe of a fish. It sometimes constitutes extensive beds, as in the European Jurassic. See the Chart of Geology.

OOLITIC; OOELITIC O`ö*lit"ic, a. Etym: [Cf.F. oölithique.]

Defn: Of or pertaining to oölite; composed of, or resembling, oölite.

OOLOGICAL; OOELOGICAL O`ö*log"ic*al, a. (Zoöl.)

Defn: Of or pertaining to oölogy.

OOLOGIST; OOELOGIST O*öl"o*gist, n.

Defn: One versed in oölogy.

OOLOGY; OOELOGY O*öl"o*gy, n. Etym: [Gr. -logy.]

Defn: The science of eggs in relation to their coloring, size, shape, and number.

OOLONG Oo"long, n. Etym: [Chinese, green dragon.]

Defn: A fragrant variety of black tea having somewhat the flavor of green tea. [Written also oulong.]

OOMIAC; OOMIAK Oo"mi*ac, Oo"mi*ak, n.

Defn: A long, broad boat used by the Eskimos.

OON Oon, a.

Defn: One. [Obs.] Chaucer.

OONES Oones, adv.

Defn: Once. [Obs.] Chaucer.

OOP Oop, v. t. Etym: [Etymol. uncertain.]

Defn: To bind with a thread or cord; to join; to unite. [Scot.] Jamieson.

OOPACK; OOPAK Oo"pack, Oo"pak, n. Etym: [So named from a district in China.]

Defn: A kind of black tea.

OOPHORE; OOEPHORE O"ö*phore, n. Etym: [Gr. (Bot.)

Defn: An alternately produced form of certain cryptogamous plants, as ferns, mosses, and the like, which bears antheridia and archegonia, and so has sexual fructification, as contrasted with the sporophore, which is nonsexual, but produces spores in countless number. In ferns the oöphore is a minute prothallus; in mosses it is the leafy plant.

OOPHORECTOMY; OOEPHORECTOMY O`ö*pho*rec"to*my, n. Etym: [Gr. (Surg.)

Defn: Ovariotomy.

OOPHORIC; OOEPHORIC O`ö*phor"ic, a. (Bot.)

Defn: Having the nature of, or belonging to, an oöphore.

OOPHORIDIUM; OOEPHORIDIUM O`ö*pho*rid"i*um, n.; pl. L. Oöphorida, E. Oöphoridiums. Etym: [NL., dim. fr. Gr. Oöphore.] (Bot.)

Defn: The macrosporangium or case for the larger kind of spores in heterosporous flowerless plants.

OOPHORITIS; OOEPHORITIS O`ö*pho*ri"tis, n. Etym: [NL., fr. Gr. -itis.] (Med.)

Defn: Ovaritis.

OOPHYTE; OOEPHYTE O"ö*phyte, n. Etym: [Gr. (Bot.)

Defn: Any plant of a proposed class or grand division (collectively termed oöphytes or Oöphyta), which have their sexual reproduction accomplished by motile antherozoids acting on oöspheres, either while included in their oögonia or after exclusion.

Note: This class was at first called Oösporeæ, and is made to include all algæ and fungi which have this kind of reproduction, however they may differ in all other respects, the contrasted classes of Thallophytes being Protophytes, Zygophytes, and Carpophytes. The whole system has its earnest advocates, but is rejected by many botanists. See Carpophyte.

OOPHYTIC; OOEPHYTIC O`ö*phyt"ic, a. (Bot.)

Defn: Of or pertaining to an oöphyte.

OORDOBA Cór"do*ba (kôr"do*vä), n. [Prob. fr. the Spanish explorer Francisco Hernández de Córdoba.]

Defn: The monetary unit of Nicaragua, equivalent to the United States gold dollar.

OORIAL; OOERIAL O*ö"ri*al, n. (Zoöl.)

Defn: A wild, bearded sheep inhabiting the Ladakh mountains. It is reddish brown, with a dark beard from the chin to the chest.

OOSPERM; OOESPERM O"ö*sperm, n. Etym: [Gr. sperm.] (Biol.)

Defn: The ovum, after fusion with the spermatozoön in impregnation. Balfour.

OOSPHERE; OOESPHERE O"ö*sphere, n. Etym: [Gr. sphere.]

1. (Bot.)

Defn: An unfertilized, rounded mass of protoplasm, produced in an oögonium.

Note: After being fertilized by the access of antherozoids it becomes covered with a cell wall and develops into an oöspore, which may grow into a new plant like the parent.

2. (Bot.)

Defn: An analogous mass of protoplasm in the ovule of a flowering plant; an embryonic vesicle. Goodale.

OOSPORANGIUM; OOESPORANGIUM O`ö*spo*ran"gi*um, n.; pl. L. Oösporangia, E. Oösporangiums. Etym: [NL., fr. Gr. (Bot.)

Defn: An oögonium; also, a case containing oval or rounded spores of some other kind than oöspores.

OOSPORE; OOESPORE O"ö*spore, n. Etym: [Gr. (Bot.) (a) A special kind of spore resulting from the fertilization of an oösphere by antherozoids. (b) A fertilized oösphere in the ovule of a flowering plant.

OOSPORIC; OOESPORIC O`ö*spor"ic, a. (Bot.)

Defn: Of or pertaining to an oöspore.

OOSTEGITE; OOESTEGITE O*ös"te*gite, n. Etym: [Gr. (Zoöl.)

Defn: One of the plates which in some Crustacea inclose a cavity wherein the eggs are hatched.

OOTHECA; OOETHECA O`ö*the"ca, n.; pl. Oöthecæ. Etym: [NL., fr. Gr. (Zoöl.)

Defn: An egg case, especially those of many kinds of mollusks, and of some insects, as the cockroach. Cf. Ooecium.

OOTOOID; OOETOOID; OOTOCOID; OOETOCOID O*öt"*ooid, O*öt"o*coid, n. Etym: [Gr. -oid.] (Zoöl.)

Defn: A half oviparous, or an oviparous, mammal; a marsupial or monotreme.

OOTYPE; OOETYPE O"ö*type, n. Etym: [Gr. -type.] (Zoöl.)

Defn: The part of the oviduct of certain trematode worms in which the ova are completed and furnished with a shell.

OOZE Ooze, n. Etym: [OE. wose, AS. wase dirt, mire, mud, akin to w juice, ooze, Icel. vas wetness, OHG. waso turf, sod, G. wasen.]

1. Soft mud or slime; earth so wet as to flow gently, or easily yield to pressure. "My son i' the ooze is bedded." Shak.

2. Soft flow; spring. Prior.

3. The liquor of a tan vat.

OOZE Ooze, v. i. [imp. & p. p. Oozed; p.pr. & vb.n. Oozing.] Etym: [Prov. Eng. weeze, wooz. See Ooze, n.]

1. To flow gently; to percolate, as a liquid through the pores of a substance or through small openings. The latent rill, scare oozing through the grass. Thomson.

2. Fig.: To leak (out) or escape slowly; as, the secret oozed out; his courage oozed out.

OOZE Ooze, v. t.

Defn: To cause to ooze. Alex. Smith.

OOZE LEATHER Ooze leather.

Defn: Leather made from sheep and calf skins by mechanically forcing ooze through them; esp., such leather with a soft, finely granulated finish (called sometimes velvet finish) put on the flesh side for special purposes. Ordinary ooze leather is used for shoe uppers, in bookbinding, etc. Hence Ooze calf, Ooze finish, etc.

OOZOA; OOEZOA O`ö*zo"a, n. pl. Etym: [NL., fr. Gr. (Zoöl.)

Defn: Same as Acrita.

OOZY Ooz"y, a.

Defn: Miry; containing soft mud; resembling ooze; as, the oozy bed of a river. Pope.

OPACATE O*pa"cate, v. t. Etym: [L. opacatus, p.p. of opacare.]

Defn: To darken; to cloud. [Obs.] Boyle.

OPACITY O*pac"i*ty, n. Etym: [L. opacitas: cf.F. opacité.]

1. The state of being opaque; the quality of a body which renders it impervious to the rays of light; want of transparency; opaqueness.

2. Obscurity; want of clearness. Bp. Hall.

OPACOUS O*pa"cous, a. Etym: [L. opacus. See Opaque.]

Defn: Opaque. [R.] Milton. -- O*pa"cous*ness, n. [R.]

OPACULAR O*pac"u*lar, a.

Defn: Opaque. [Obs.] Sterne.

OPAH O"pah, n. (Zoöl.)

Defn: A large oceanic fish (Lampris quttatus), inhabiting the Atlantic Ocean. It is remarkable for its brilliant colors, which are red, green, and blue, with tints of purple and gold, covered with round silvery spots. Called also king of the herrings.

OPAKE O*pake", a.

Defn: See Opaque.

OPAL O"pal, n. Etym: [L. opalus: cf. Gr. upala a rock, stone, precious stone: cf. F. opale.] (Min.)

Defn: A mineral consisting, like quartz, of silica, but inferior to quartz in hardness and specific gravity.

Note: The precious opal presents a peculiar play of colors of delicate tints, and is highly esteemed as a gem. One kind, with a varied play of color in a reddish ground, is called the harlequin opal. The fire opal has colors like the red and yellow of flame. Common opal has a milky appearance. Menilite is a brown impure variety, occurring in concretions at Menilmontant, near Paris. Other varieties are cacholong, girasol, hyalite, and geyserite.

OPALESCE O`pal*esce", v. i. [imp. & p. p. Opalesced; p. pr. & vb. n. Opalescing.]

Defn: To give forth a play of colors, like the opal.

OPALESCENCE O`pal*es"cence, n. (Min.)

Defn: A reflection of a milky or pearly light from the interior of a mineral, as in the moonstone; the state or quality of being opalescent.

OPALESCENT O`pal*es"cent, a.

Defn: Reflecting a milky or pearly light from the interior; having an opaline play of colors.

OPALINE O"pal*ine, a. Etym: [Cf. F. opalin.]

Defn: Of, pertaining to, or like, opal in appearance; having changeable colors like those of the opal.

OPALIZE O"pal*ize, v. t. [imp. & p. p. Opalized; p. pr. & vb. n. Opalizing.] Etym: [Cf. F. opaliser.]

Defn: To convert into opal, or a substance like opal. Lyell.

OPALOTYPE O*pal"o*type, n. Etym: [Opal + -type.] (Photog.)

Defn: A picture taken on "milky" glass.

OPAQUE O*paque", a. Etym: [F., fr. L. opacus. Cf. Opacous.]

1. Impervious to the rays of light; not transparent; as, an opaque substance.

2. Obscure; not clear; unintelligible. [Colloq.]

OPAQUE O*paque", n.

Defn: That which is opaque; opacity. Young.

OPAQUENESS O*paque"ness, n.

Defn: The state or quality of being impervious to light; opacity. Dr. H. More.

OPE Ope, a.

Defn: Open. [Poetic] Spenser. On Sunday heaven's gate stands ope. Herbert.

OPE Ope, v. t. & i.

Defn: To open. [Poetic] Wilt thou not ope thy heart to know What rainbows teach and sunsets show Emerson.

OPEIDOSCOPE O*pei"do*scope, n. Etym: [Gr. -scope.] (Physics)

Defn: An instrument, consisting of a tube having one end open and the other end covered with a thin flexible membrance to the center of which is attached a small mirror. It is used for exhibiting upon a screen, by means of rays reflected from the mirror, the vibratory motions caused by sounds produced at the open end of the tube, as by speaking or singing into it. A. E. Dolbear.

OPELET Ope"let, n. (Zoöl.)

Defn: A bright-colored European actinian (Anemonia, or Anthea, sulcata); -- so called because it does not retract its tentacles.

OPEN O"pen, a. Etym: [AS. open; akin to D. open, OS. opan, G. offan, Icel. opinn, Sw. öppen, Dan. aaben, and perh. to E. up. Cf. Up, and Ope.]

1. Free of access; not shut up; not closed; affording unobstructed ingress or egress; not impeding or preventing passage; not locked up or covered over; -- applied to passageways; as, an open door, window, road, etc.; also, to inclosed structures or objects; as, open houses, boxes, baskets, bottles, etc.; also, to means of communication or approach by water or land; as, an open harbor or roadstead. Through the gate, Wide open and unquarded, Satan passed. Milton

Note: Also, figuratively, used of the ways of communication of the mind, as by the senses; ready to hear, see, etc.; as, to keep one's eyes and ears open. His ears are open unto their cry. Ps. xxxiv. 15.

2. Free to be used, enjoyed, visited, or the like; not private; public; unrestricted in use; as, an open library, museum, court, or other assembly; liable to the approach, trespass, or attack of any one; unprotected; exposed. If Demetrius . . . have a matter against any man, the law is open and there are deputies. Acts xix. 33. The service that I truly did his life, Hath left me open to all injuries. Shak.

3. Free or cleared of obstruction to progress or to view; accessible; as, an open tract; the open sea.

4. Not drawn together, closed, or contracted; extended; expanded; as, an open hand; open arms; an open flower; an open prospect. Each, with open arms, embraced her chosen knight. Dryden.

5. Hence: (a) Without reserve or false pretense; sincere; characterized by sincerity; unfeigned; frank; also, generous; liberal; bounteous; -- applied to personal appearance, or character, and to the expression of thought and feeling, etc. With aspect open, shall erect his head. Pope. The Moor is of a free and open nature. Shak. The French are always open, familiar, and talkative. Addison.

(b) Not concealed or secret; not hidden or disguised; exposed to view or to knowledge; revealed; apparent; as, open schemes or plans; open shame or guilt. His thefts are too open. Shak. That I may find him, and with secret gaze Or open admiration him behold. Milton.

6. Not of a quality to prevent communication, as by closing water ways, blocking roads, etc.; hence, not frosty or inclement; mild; -- used of the weather or the climate; as, an open season; an open winter. Bacon.

7. Not settled or adjusted; not decided or determined; not closed or withdrawn from consideration; as, an open account; an open question; to keep an offer or opportunity open.

8. Free; disengaged; unappropriated; as, to keep a day open for any purpose; to be open for an engagement.

9. (Phon.) (a) Uttered with a relatively wide opening of the articulating organs; -- said of vowels; as, the än fär is open as compared with the a in say. (b) Uttered, as a consonant, with the oral passage simply narrowed without closure, as in uttering s.

10. (Mus.) (a) Not closed or stopped with the finger; -- said of the string of an instrument, as of a violin, when it is allowed to vibrate throughout its whole length. (b) Produced by an open string; as, an open tone. The open air, the air out of doors. -- Open chain. (Chem.) See Closed chain, under Chain. -- Open circuit (Elec.), a conducting circuit which is incomplete, or interrupted at some point; -- opposed to an uninterrupted, or Ant: closed circuit. -- Open communion, communion in the Lord's supper not restricted to persons who have been baptized by immersion. Cf. Close communion, under Close, a. -- Open diapason (Mus.), a certain stop in an organ, in which the pipes or tubes are formed like the mouthpiece of a flageolet at the end where the wind enters, and are open at the other end. -- Open flank (Fort.), the part of the flank covered by the orillon. -- Open-front furnace (Metal.), a blast furnace having a forehearth. -- Open harmony (Mus.), harmony the tones of which are widely dispersed, or separated by wide intervals. -- Open hawse (Naut.), a hawse in which the cables are parallel or slightly divergent. Cf. Foul hawse, under Hawse. -- Open hearth (Metal.), the shallow hearth of a reverberatory furnace. -- Open-hearth furnace, a reverberatory furnace; esp., a kind of reverberatory furnace in which the fuel is gas, used in manufacturing steel. -- Open-hearth process (Steel Manuf.), a process by which melted cast iron is converted into steel by the addition of wrought iron, or iron ore and manganese, and by exposure to heat in an open-hearth furnace; -- also called the Siemens-Martin process, from the inventors. -- Open-hearth steel, steel made by an open-hearth process; -- also called Siemens-Martin steel. -- Open newel. (Arch.) See Hollow newel, under Hollow. -- Open pipe (Mus.), a pipe open at the top. It has a pitch about an octave higher than a closed pipe of the same length. -- Open-timber roof (Arch.), a roof of which the constructional parts, together with the under side of the covering, or its lining, are treated ornamentally, and left to form the ceiling of an apartment below, as in a church, a public hall, and the like. -- Open vowel or consonant. See Open, a., 9.

Note: Open is used in many compounds, most of which are self- explaining; as, open-breasted, open-minded.

Syn. -- Unclosed; uncovered; unprotected; exposed; plain; apparent; obvious; evident; public; unreserved; frank; sincere; undissembling; artless. See Candid, and Ingenuous.

OPEN O"pen, n.

Defn: Open or unobstructed space; clear land, without trees or obstructions; open ocean; open water. "To sail into the open." Jowett (Thucyd. ). Then we got into the open. W. Black. In open, in full view; without concealment; openly. [Obs.] Beau. & Fl.

OPEN O"pen v. t. [imp. & p. p. Opened; p. pr. & vb. n. Opening.] Etym: [AS. openian. See Open,a.]

1. To make or set open; to render free of access; to unclose; to unbar; to unlock; to remove any fastening or covering from; as, to open a door; to open a box; to open a room; to open a letter. And all the windows of my heart I open to the day. Whittier.

2. To spread; to expand; as, to open the hand.

3. To disclose; to reveal; to interpret; to explain. The king opened himself to some of his council, that he was sorry for the earl's death. Bacon. Unto thee have I opened my cause. Jer. xx. 12. While he opened to us the Scriptures. Luke xxiv. 32.

4. To make known; to discover; also, to render available or accessible for settlements, trade, etc. The English did adventure far for to open the North parts of America. Abp. Abbot.

5. To enter upon; to begin; as, to open a discussion; to open fire upon an enemy; to open trade, or correspondence; to open a case in court, or a meeting.

6. To loosen or make less compact; as, to open matted cotton by separating the fibers. To open one's mouth, to speak. -- To open up, to lay open; to discover; to disclose. Poetry that had opened up so many delightful views into the character and condition of our "bold peasantry, their country's pride." Prof. Wilson.

OPEN O"pen, v. i.

1. To unclose; to form a hole, breach, or gap; to be unclosed; to be parted. The earth opened and swallowed up Dathan, and covered the company of Abiram. Ps. cvi. 17.

2. To expand; to spread out; to be disclosed; as, the harbor opened to our view.

3. To begin; to commence; as, the stock opened at par; the battery opened upon the enemy.

4. (Sporting)

Defn: To bark on scent or view of the game.

OPEN-AIR O"pen-air`, a.

Defn: Taking place in the open air; outdoor; as, an open-air game or meeting.

OPENBILL O"pen*bill`, n. (Zoöl.)

Defn: A bird of the genus Anastomus, allied to the stork; -- so called because the two parts of the bill touch only at the base and tip. One species inhabits India, another Africa. Called also open- beak. See Illust. (m), under Beak.

OPEN DOOR O"pen door. (a) Open or free admission to all; hospitable welcome; free opportunity.

She of the open soul and open door, With room about her hearth for all mankind. Lowell.

(b) In modern diplomacy, opportunity for political and commercial intercourse open to all upon equal terms, esp. with reference to a nation whose policy is wholly or partially fixed by nations foreign to itself, or to territory newly acquired by a conquering nation. In this sense, often used adjectively, as, open-door system, open-door policy, etc.

The steps taken by Britain to maintain the open door have so far proved to be perfectly futile. A. R. Colquhoun.

OPENER O"pen*er, n.

Defn: One who, or that which, opens. "True opener of my eyes." Milton.

OPEN-EYED O"pen-eyed`, a.

Defn: With eyes widely open; watchful; vigilant. Shak.

OPEN-HANDED O"pen-hand`ed, a.

Defn: Generous; liberal; munificent. -- O"pen-hand`ed*ness, n. J. S. Mill.

OPEN-HEADED O"pen-head`ed, a.

Defn: Bareheaded. [Obs.]

OPEN-HEARTED O"pen-heart`ed, a.

Defn: Candid; frank; generous. Dryden. -- O"pen-heart`ed*ly, adv. -- O"pen-heart`ed*ness, n. Walton.

OPEN-HEARTH STEEL Open-hearth steel.

Defn: See under Open.

OPENING O"pen*ing, n.

1. The act or process of opening; a beginning; commencement; first appearance; as, the opening of a speech. The opening of your glory was like that of light. Dryden.

2. A place which is open; a breach; an aperture; a gap; cleft, or hole. We saw him at the opening of his tent. Shak.

3. Hence: A vacant place; an opportunity; as, an opening for business. [Colloq.] Dickens.

4. A thinly wooded space, without undergrowth, in the midst of a forest; as, oak openings. [U.S.] Cooper.

OPENLY O"pen*ly, adv. Etym: [AS. openlice.]

1. In an open manner; publicly; not in private; without secrecy. How grossly and openly do many of us contradict the precepts of the gospel by our ungodliness! Tillotson.

2. Without reserve or disguise; plainly; evidently. My love . . . shall show itself more openly. Shak.

OPEN-MOUTHED O"pen-mouthed`, a.

Defn: Having the mouth open; gaping; hence, greedy; clamorous. L'Estrange.

OPENNESS O"pen*ness, n.

Defn: The quality or state of being open.

OPEN SEA Open sea. (Internat. Law)

Defn: A sea open to all nations. See Mare clausum.

OPEN VERDICT Open verdict. (Law)

Defn: A verdict on a preliminary investigation, finding the fact of a crime but not stating the criminal, or finding the fact of a violent death without disclosing the cause.

OPENWORK O"pen*work`, n.

1. Anything so constructed or manufactured (in needlework, carpentry, metal work, etc.) as to show openings through its substance; work that is perforated or pierced.

2. (Mining)

Defn: A quarry; an open cut. Raymond.

OPERA Op"er*a, n. Etym: [It., fr. opera work, composition, opposed to an improvisation, fr. L. opera pains work, fr. opus, operis, work, labor: cf. F. opéra. See Operate.]

1. A drama, either tragic or comic, of which music forms an essential part; a drama wholly or mostly sung, consisting of recitative, arials, choruses, duets, trios, etc., with orchestral accompaniment, preludes, and interludes, together with appropriate costumes, scenery, and action; a lyric drama.

2. The score of a musical drama, either written or in print; a play set to music.

3. The house where operas are exhibited. Opéra bouffe Etym: [F. opéra opera + bouffe comic, It.buffo], Opera buffa Etym: [It.], light, farcical, burlesque opera. -- Opera box, a partially inclosed portion of the auditorium of an opera house for the use of a small private party. -- Opéra comique Etym: [F.], comic or humorous opera. -- Opera flannel, a light flannel, highly finished. Knight. -- Opera girl (Bot.), an East Indian plant (Mantisia saltatoria) of the Ginger family, sometimes seen in hothouses. It has curious flowers which have some resemblance to a ballet dancer, whence the popular name. Called also dancing girls. -- Opera glass, a short telescope with concave eye lenses of low power, usually made double, that is, with a tube and set of glasses for each eye; a lorgnette; -- so called because adapted for use at the opera, theater, etc. -- Opera hat, a gentleman's folding hat. -- Opera house, specifically, a theater devoted to the performance of operas. -- Opera seria Etym: [It.], serious or tragic opera; grand opera.

OPERABLE Op"er*a*ble, a.

Defn: Practicable. [Obs.]

OPERAMETER Op`er*am"e*ter, n. Etym: [L. opus, operis, pl. opera work + -meter.]

Defn: An instrument or machine for measuring work done, especially for ascertaining the number of rotations made by a machine or wheel in manufacturing cloth; a counter. Ure.

OPERANCE; OPERANCY Op"er*ance, Op"er*an*cy, n.

Defn: The act of operating or working; operation. [R.]

OPERAND Op"er*and, n. Etym: [From neuter of L. operandus, gerundive of operari. See Operate.] (Math.)

Defn: The symbol, quantity, or thing upon which a mathematical operation is performed; -- called also faciend.

OPERANT Op"er*ant, a. Etym: [L. operans, p.pr. of operari. See Operate.]

Defn: Operative. [R.] Shak. -- n.

Defn: An operative person or thing. [R.] Coleridge.

OPERATE Op"er*ate, v. i. [imp. & p. p. Operated; p. pr. & vb. n. Operating.] Etym: [L. operatus, p.p. of operari to work, fr. opus, operis, work, labor; akin to Skr. apas, and also to G. üben to exercise, OHG. uoben, Icel. . Cf. Inure, Maneuver, Ure.]

1. To perform a work or labor; to exert power or strengh, physical or mechanical; to act.

2. To produce an appropriate physical effect; to issue in the result designed by nature; especially (Med.), to take appropriate effect on the human system.

3. To act or produce effect on the mind; to exert moral power or influence. The virtues of private persons operate but on a few. Atterbury. A plain, convincing reason operates on the mind both of a learned and ignorant hearer as long as they live. Swift.

4. (Surg.)

Defn: To perform some manual act upon a human body in a methodical manner, and usually with instruments, with a view to restore soundness or health, as in amputation, lithotomy, etc.

5. To deal in stocks or any commodity with a view to speculative profits. [Brokers' Cant]

OPERATE Op"er*ate, v. t.

1. To produce, as an effect; to cause. The same cause would operate a diminution of the value of stock. A. Hamilton.

2. To put into, or to continue in, operation or activity; to work; as, to operate a machine.

OPERATIC; OPERATICAL Op`er**at"ic, Op`er*at"ic*al, a.

Defn: Of or pertaining to the opera or to operas; characteristic of, or resembling, the opera.

OPERATION Op`er*a"tion, n. Etym: [L. operatio: cf. F. opération.]

1. The act or process of operating; agency; the exertion of power, physical, mechanical, or moral. The pain and sickness caused by manna are the effects of its operation on the stomach. Locke. Speculative painting, without the assistance of manual operation, can never attain to perfection. Dryden.

2. The method of working; mode of action.

3. That which is operated or accomplished; an effect brought about in accordance with a definite plan; as, military or naval operations.

4. Effect produced; influence. [Obs.] The bards . . . had great operation on the vulgar. Fuller.

5. (Math.)

Defn: Something to be done; some transformation to be made upon quantities, the transformation being indicated either by rules or symbols.

6. (Surg.)

Defn: Any methodical action of the hand, or of the hand with instruments, on the human body, to produce a curative or remedial effect, as in amputation, etc. Calculus of operations. See under Calculus.

OPERATIVE Op"er*a*tive, a. Etym: [Cf.L. operativus, F. opératif.]

1. Having the power of acting; hence, exerting force, physical or moral; active in the production of effects; as, an operative motive. It holds in all operative principles. South.

2. Producing the appropriate or designed effect; efficacious; as, an operative dose, rule, or penalty.

3. (Surg.)

Defn: Based upon, or consisting of, an operation or operations; as, operative surgery.

OPERATIVE Op"er*a*tive, n.

Defn: A skilled worker; an artisan; esp., one who operates a machine in a mill or manufactory.

OPERATIVELY Op"er*a*tive*ly, adv.

Defn: In an operative manner.

OPERATOR Op"er*a`tor, n. Etym: [L.]

1. One who, or that which, operates or produces an effect.

2. (Surg.)

Defn: One who performs some act upon the human body by means of the hand, or with instruments.

3. A dealer in stocks or any commodity for speculative purposes; a speculator. [Brokers' Cant]

4. (Math.)

Defn: The symbol that expresses the operation to be performed; -- called also facient.

OPERATORY Op"er*a*to*ry, n.

Defn: A laboratory. [Obs.]

OPERCLE O"per*cle, n. Etym: [Cf.F. opercule. See Operculum.]

1. (Anat.)

Defn: Any one of the bony plates which support the gill covers of fishes; an opercular bone.

2. (Zoöl.)

Defn: An operculum.

OPERCULA O*per"cu*la, n. pl.

Defn: See Operculum.

OPERCULAR O*per"cu*lar, a.

Defn: Of, pertaining to, or like, an operculum.

OPERCULAR O*per"cu*lar, n. (Anat.)

Defn: The principal opercular bone or operculum of fishes.

OPERCULATE; OPERCULATED O*per"cu*late, O*per"cu*la`ted, a. Etym: [L. operculatus, p.p. of operculare to furnish with a lid, fr. operculum lid.]

1. (Bot.)

Defn: Closed by a lid or cover, as the capsules of the mosses.

2. (Zoöl.)

Defn: Having an operculum, or an apparatus for protecting the gills; -- said of shells and of fishes.

OPERCULIFEROUS O*per`cu*lif"er*ous, a. Etym: [Operculum + -ferous.] (Zoöl.)

Defn: Bearing an operculum.

OPERCULIFORM O*per"cu*li*form, a. Etym: [L. operculum a cover + -form: cf. F. operculiforme.]

Defn: Having the form of a lid or cover.

OPERCULIGENOUS O*per`cu*lig`e*nous, a. Etym: [Operculum + -genous.] (Zoöl.)

Defn: Producing an operculum; -- said of the foot, or part of the foot, of certain mollusks.

OPERCULUM O*per"cu*lum, n.; pl. L. Opercula, E. Operculums. Etym: [L., a cover or lid, fr. operire to cover.]

1. (Bot.) (a) The lid of a pitcherform leaf. (b) The lid of the urnlike capsule of mosses.

2. (Anat.) (a) Any lidlike or operculiform process or part; as, the opercula of a dental follicle. (b) The fold of integument, usually supported by bony plates, which protects the gills of most fishes and some amphibians; the gill cover; the gill lid. (c) The principal opercular bone in the upper and posterior part of the gill cover.

3. (Zoöl.) (a) The lid closing the aperture of various species of shells, as the common whelk. See Illust. of Gastropoda. (b) Any lid-shaped structure closing the aperture of a tube or shell.

OPERETTA Op`er*et"ta, n. Etym: [It., dim. of opera.] (Mus.)

Defn: A short, light, musical drama.

OPEROSE Op"er*ose`. a. Etym: [L. operosus, fr. opera pains, labor, opus, operis, work, labor.]

Defn: Wrought with labor; requiring labor; hence, tedious; wearisome. "Operose proceeding." Burke. "A very operose calculation." De Quincey. -- Op"er*ose`ly, adv. -- Op"er*ose`ness, n.

OPEROSITY Op`er*os"i*ty, n. Etym: [L. operositas.]

Defn: Laboriousness. [R.] Bp. Hall.

OPEROUS Op"er*ous, a.

Defn: Operose. [Obs.] Holder. -- Op"er*ous*ly, adv. [Obs.]

OPERTANEOUS Op`er*ta"ne*ous, a. Etym: [L. opertaneus; operire to hide.]

Defn: Concealed; private. [R.]

OPETIDE Ope"tide`, n. Etym: [Ope + tide.]

Defn: Open time; -- applied to different things: (a) The early spring, or the time when flowers begin opening. [Archaic] Nares. (b) The time between Epiphany and Ash Wednesday wherein marriages were formerly solemnized publicly in churches. [Eng.] (c) The time after harvest when the common fields are open to all kinds of stock. [Prov.Eng.] Halliwell. [Written also opentide.]

OPHELIC O*phel"ic, a. (Chem.)

Defn: Of, pertaining to, or designating, a substance (called ophelic acid) extracted from a plant (Ophelia) of the Gentian family as a bitter yellowish sirup, used in India as a febrifuge and tonic.

OPHICLEIDE Oph"i*cleide, n. Etym: [F. ophicléide, fr. Gr. (Mus.)

Defn: A large brass wind instrument, formerly used in the orchestra and in military bands, having a loud tone, deep pitch, and a compass of three octaves; -- now generally supplanted by bass and contrabass tubas. Moore (Encyc. of Music).

OPHIDIA O*phid"i*a, n. pl. Etym: [NL., fr. Gr. (Zoöl.)

Defn: The order of reptiles which includes the serpents.

Note: The most important divisions are: the Solenoglypha, having erectile perforated fangs, as the rattlesnake; the Proteroglypha, or elapine serpents, having permanently erect fang, as the cobra; the Asinea, or colubrine serpents, which are destitute of fangs; and the Opoterodonta, or Epanodonta, blindworms, in which the mouth is not dilatable.

OPHIDIAN O*phid"i*an, n. Etym: [Cf. F. ophidien.] (Zoöl.)

Defn: One of the Ophidia; a snake or serpent.

OPHIDIAN O*phid"i*an, a. Etym: [Cf. F. ophidien.] (Zoöl.)

Defn: Of or pertaining to the Ophidia; belonging to serpents.

OPHIDIOID O*phid"i*oid, a. Etym: [Ophidion + -oid.] (Zoöl.)

Defn: Of or pertaining to the Ophidiidæ, a family of fishes which includes many slender species. -- n.

Defn: One of the Ophidiidæ.

OPHIDION O*phid"i*on, n.; pl. Ophidia. Etym: [L., fr. Gr. (Zoöl.)

Defn: The typical genus of ophidioid fishes. [Written also Ophidium.] See Illust. under Ophidioid.

OPHIDIOUS O*phid"i*ous, a.

Defn: Ophidian.

OPHIOLATRY O`phi*ol"a*try, n. Etym: [Gr.

Defn: The worship of serpents.

OPHIOLOGIC; OPHIOLOGICAL O`phi*o*log"ic, O`phi*o*log"ic*al, a.

Defn: Of or pertaining to ophiology.

OPHIOLOGIST O`phi*ol"o*gist, n.

Defn: One versed in the natural history of serpents.

OPHIOLOGY O`phi*ol"o*gy, n. Etym: [Gr. -logy: cf.F. ophioloqie.]

Defn: That part of natural history which treats of the ophidians, or serpents.

OPHIOMANCY O"phi*o*man`cy, n. Etym: [Gr. -mancy: cf. F. ophiomantie.]

Defn: Divination by serpents, as by their manner of eating, or by their coils.

OPHIOMORPHA O`phi*o*mor"pha, n. pl. Etym: [NL. See Ophiomorphous.] (Zoöl.)

Defn: An order of tailless amphibians having a slender, wormlike body with regular annulations, and usually with minute scales imbedded in the skin. The limbs are rudimentary or wanting. It includes the cæcilians. Called also Gymnophiona and Ophidobatrachia.

OPHIOMORPHITE O`phi*o*mor"phite, n. Etym: [Gr. (Paleon.)

Defn: An ammonite.

OPHIOMORPHOUS O`phi*o*mor"phous, a. Etym: [Gr. -morphous.]

Defn: Having the form of a serpent.

OPHIOPHAGOUS O`phi*oph"a*gous, a. Etym: [Gr. ophiophage.] (Zoöl.)

Defn: Feeding on serpents; -- said of certain birds and reptiles.

OPHIOPHAGUS O`phi*oph"a*gus, n. Etym: [NL. See Ophiophagous.] (Zoöl.)

Defn: A genus of venomous East Indian snakes, which feed on other snakes. Ophiophagus elaps is said to be the largest and most deadly of poisonous snakes.

OPHISM Oph"ism, n.

1. Doctrines and rites of the Ophites.

2. Serpent worship or the use of serpents as magical agencies.

OPHITE O"phite, a. Etym: [Gr.

Defn: Of or pertaining to a serpent. [Obs.]

OPHITE O"phite, n. Etym: [L. ophites, Gr. ophite.] (Min.)

Defn: A greenish spotted porphyry, being a diabase whose pyroxene has been altered to uralite; -- first found in the Pyreness. So called from the colored spots which give it a mottled appearance. -- O*phi"ic, a.

OPHITE O"phite, n. Etym: [L. Ophitae, pl. See Ophite, a.] (Eccl.Hist.)

Defn: A mamber of a Gnostic serpent-worshiping sect of the second century.

OPHIUCHUS O`phi*u"chus, n. Etym: [L., fr. Gr. (Astron.)

Defn: A constellation in the Northern Hemisphere, delineated as a man holding a serpent in his hands; -- called also Serpentarius.

OPHIURA O`phi*u"ra, n. Etym: [NL., from Gr. (Zoöl.)

Defn: A genus of ophiurioid starfishes.

OPHIURAN O`phi*u"ran, a. (Zoöl.)

Defn: Of or pertaining to the Ophiurioidea. -- n.

Defn: One of the Ophiurioidea.

OPHIURID O`phi*u"rid, n. (Zoöl.)

Defn: Same as Ophiurioid.

OPHIURIDA O`phi*u"ri*da, n. pl. Etym: [NL.] (Zoöl.)

Defn: Same as Ophiurioidea.

OPHIURIOID O`phi*u"ri*oid, a. (Zoöl.)

Defn: Of or pertaining to the Ophiurioidea. -- n.

Defn: One of the Ophiurioidea. [Written also ophiuroid.]

OPHIURIOIDEA; OPHIUROIDEA O`phi*u`ri*oi"de*a, O`phi*u*roi"de*a, n. pl. Etym: [NL., fr. Gr. (Zoöl.)

Defn: A class of star-shaped echinoderms having a disklike body, with slender, articulated arms, which are not grooved beneath and are often very fragile; -- called also Ophiuroida and Ophiuridea. See Illust. under Brittle star.

OPHRYON Oph"ry*on, n. Etym: [NL., fr. Gr. (Anat.)

Defn: The supraorbital point.

OPHTHALMIA Oph*thal"mi*a, n. Etym: [F. ophthalmie, L. ophthalmia, fr. Gr. optic. See Optic.] (Med.)

Defn: An inflammation of the membranes or coats of the eye or of the eyeball.

OPHTHALMIC Oph*thal"mic, a. Etym: [Gr. ophthalmique. See Ophthalmia.] (Anat.)

Defn: Of, pertaining to, or in the region of, the eye; ocular; as the ophthalmic, or orbitonasal, nerve, a division of the trigeminal, which gives branches to the lachrymal gland, eyelids, nose, and forehead. Ophthalmic region (Zoöl.), the space around the eyes.

OPHTHALMITE Oph*thal"mite, n. Etym: [Gr. (Zoöl.)

Defn: An eyestalk; the organ which bears the compound eyes of decapod Crustacea.

OPHTHALMOLOGICAL Oph*thal`mo*log"ic*al, a.

Defn: Of or pertaining to ophthalmology.

OPHTHALMOLOGIST Oph`thal*mol"o*gist, n.

Defn: One skilled in ophthalmology; an oculist.

OPHTHALMOLOGY Oph`thal*mol"o*gy, n. Etym: [Gr. -logy: cf. F. ophthalmologie.]

Defn: The science which treats of the structure, functions, and diseases of the eye.

OPHTHALMOMETER Oph`thal*mom"e*ter, n. Etym: [Gr. -meter.] (Physiol.)

Defn: An instrument devised by Helmholtz for measuring the size of a reflected image on the convex surface of the cornea and lens of the eye, by which their curvature can be ascertained.

OPHTHALMOSCOPE Oph*thal"mo*scope, n. Etym: [From Gr. -scope.] (Physiol.)

Defn: An instrument for viewing the interior of the eye, particularly the retina. Light is thrown into the eye by a mirror (usually concave) and the interior is then examined with or without the aid of a lens. -- Oph*thal`mo*scop"ic, a.

OPHTHALMOSCOPY Oph`thal*mos"co*py, n. Etym: [Cf. F. ophthalmoscopie.]

1. A branch of physiognomy which deduces the knowledge of a person's temper and character from the appearance of the eyes.

2. Examination of the eye with the ophthalmoscope.

OPHTHALMY Oph*thal"my, n.

Defn: Same as Ophthalmia.

OPIANIC O`pi*an"ic, a. Etym: [From Opium.] (Chem.)

Defn: Of, pertaining to, or designating, an organic acid obtained by the oxidation of narcotine.

OPIANINE O"pi*a*nine, n. (Chem.)

Defn: An alkaloid found in small quantity in opium. It is identical with narcotine.

OPIANYL O"pi*a*nyl, n. Etym: [Opianic + -yl.] (Chem.)

Defn: Same as Meconin.

OPIATE O"pi*ate, n. Etym: [From Opium: cf.F. opiat.]

1. Originally, a medicine of a thicker consistence than sirup, prepared with opium. Parr.

2. Any medicine that contains opium, and has the quality of inducing sleep or repose; a narcotic.

3. Anything which induces rest or inaction; that which quiets uneasiness. They chose atheism as an opiate. Bentley.

OPIATE O"pi*ate, a. Etym: [See Opium.]

Defn: Inducing sleep; somniferous; narcotic; hence, anodyne; causing rest, dullness, or inaction; as, the opiate rod of Hermes. Milton.

OPIATE O"pi*ate, v. t.

Defn: To subject to the influence of an opiate; to put to sleep. [R.] Fenton.

OPIATED O"pi*a`ted, a.

1. Mixed with opiates.

2. Under the influence of opiates.

OPIE O"pie, n.

Defn: Opium. [Obs.] Chaucer.

OPIFEROUS O*pif"er*ous, a. Etym: [L. opifer; ops, opis, help + ferre to bear.]

Defn: Bringing help. [R.]

OPIFICE Op"i*fice, n. Etym: [L. opificium, fr. opifex workman. See Office.]

Defn: Workmanship. [Obs.] Bailey.

OPIFICER O*pif"i*cer, n.

Defn: An artificer; a workman. [Obs.] "The almighty opificer." Bentley.

OPINABLE O*pin"a*ble, a. Etym: [L. opinabilis.]

Defn: Capable of being opined or thought. Holland.

OPINATION Op`i*na"tion, n. Etym: [L. opinatio. See Opine,]

Defn: The act of thinking; a supposition. [Obs.]

OPINATIVE O*pin"a*tive, a.

Defn: Obstinate in holding opinions; opinionated. [Obs.] -- O*pin"a*tive*ly, adv. [Obs.] Burton. Sir T. More.

OPINATOR Op"i*na`tor, n. Etym: [L.]

Defn: One fond of his own opinious; one who holds an opinion. [Obs.] Glanvill.

OPINE O*pine", v. t. & i. [imp. & p. p. Opined; p. pr. & vb. n. Opining.] Etym: [L. opinari, p.p. opinatus; akin to opinus (in comp.) thinking, and perh. to E. apt: cf. F. opiner.]

Defn: To have an opinion; to judge; to think; to suppose. South.

OPINER O*pin"er, n.

Defn: One who opines. Jer. Taylor.

OPINIASTER; OPINIATRE O`pin*ias"ter, O`pin*ia"tre, a. Etym: [OF. opiniastre, F. opiniâtre. See Opinion.]

Defn: Opinionated. [Obs.] Sir W. Raleigh.

OPINIASTROUS O`pin*ias"trous, a.

Defn: See Opiniaster. [Obs.].

OPINIATE O*pin"i`ate, v. t.

Defn: To hold or maintain persistently. [Obs.] Barrow.

OPINIATED O*pin"ia*ted, a.

Defn: Opinionated. [Obs.]

OPINIATIVE O*pin"ia*tive, a.

Defn: Opinionative. Glanvill. -- O*pin"ia*tive*ly, adv. -- O*pin"ia*tive*ness, n.

OPINIATOR; OPINIATRE O`pin*ia"tor, O`pin*ia"tre, n.

Defn: One who is opinionated. [Obs.] South. Barrow.

OPINIATRE O`pin*ia"tre, a.

Defn: See Opiniaster. [Obs.] Locke.

OPINIATRETY O`pin*iat"re*ty, n. Etym: [Cf. F. opiniâtreté.]

Defn: Obstinacy in opinious. [Written also opiniatry.] [Obs.]

OPINICUS O*pin"i*cus (, n. (Her.)

Defn: An imaginary animal borne as a charge, having wings, an eagle's head, and a short tail; -- sometimes represented without wings.

OPINING O*pin"ing, n.

Defn: Opinion. [Obs.] Jer. Taylor.

OPINION O*pin"ion, n. Etym: [F., from L. opinio. See Opine.]

1. That which is opined; a notion or conviction founded on probable evidence; belief stronger than impression, less strong than positive knowledge; settled judgment in regard to any point of knowledge or action. Opinion is when the assent of the understanding is so far gained by evidence of probability, that it rather inclines to one persussion than to another, yet not without a mixture of incertainty or doubting. Sir M. Hale. I can not put off my opinion so easily. Shak.

2. The judgment or sentiment which the mind forms of persons or things; estimation. I have bought golden opinions from all sorts of people. Shak. Friendship . . . gives a man a peculiar right and claim to the good opinion of his friend. South. However, I have no opinion of those things. Bacon.

3. Favorable estimation; hence, consideration; reputation; fame; public sentiment or esteem. [Obs.] Thou hast redeemed thy lost opinion. Shak. This gained Agricola much opinion, who . . . had made such early progress into laborious . . . enterprises. Milton.

4. Obstinacy in holding to one's belief or impression; opiniativeness; conceitedness. [Obs.] Shak.

5. (Law.)

Defn: The formal decision, or expression of views, of a judge, an umpire, a counselor, or other party officially called upon to consider and decide upon a matter or point submitted. To be of opinion, to think; to judge. -- To hold opinion with, to agree with. [Obs.] Shak.

Syn. -- Sentiment; notion; persuasion; idea; view; estimation. See Sentiment.

OPINION O*pin"ion, v. t.

Defn: To opine. [Obs.]

OPINIONABLE O*pin"ion*a*ble, a.

Defn: Being, or capable of being, a matter of opinion; that can be thought; not positively settled; as, an opinionable doctrine. C. J. Ellicott.

OPINIONATE O*pin"ion*ate, a.

Defn: Opinionated.

OPINIONATED O*pin"ion*a`ted, a.

Defn: Stiff in opinion; firmly or unduly adhering to one's own opinion or to preconceived notions; obstinate in opinion. Sir W. Scott.

OPINIONATELY O*pin"ion*ate*ly, adv.

Defn: Conceitedly. Feltham.

OPINIONATIST O*pin"ion*a*tist, n.

Defn: An opinionist. [Obs.]

OPINIONATIVE O*pin"ion*a*tive, a.

1. Unduly attached to one's own opinions; opinionated. Milton.

2. Of the nature of an opinion; conjectured. [Obs.] "Things both opinionative and practical." Bunyan. -- O*pin"ion*a*tive*ly, adv. -- O*pin"ion*a*tive*ness, n.

OPINIONATOR O*pin"ion*a`tor, n.

Defn: An opinionated person; one given to conjecture. [Obs.] South.

OPINIONED O*pin"ioned, a.

Defn: Opinionated; conceited. His opinioned zeal which he thought judicious. Milton.

OPINIONIST O*pin"ion*ist, n. Etym: [Cf. F. opinioniste.]

Defn: One fond of his own notions, or unduly attached to his own opinions. Glanvill.

OPIPAROUS O*pip"a*rous, a. Etym: [L. opiparus, fr. ops, opis, riches + parare to provide.]

Defn: Sumptuous. [Obs.] -- O*pip"a*rous*ly, adv. [Obs.] E. Waterhouse.

OPISOMETER Op`i*som"e*ter, n. Etym: [Gr. -meter.]

Defn: An instrument with a revolving wheel for measuring a curved line, as on a map.

OPISTHION O*pis"thi*on, n. Etym: [NL., fr. Gr. (Anat.)

Defn: The middle of the posterior, or dorsal, margin of the great foramen of the skull.

OPISTHOBRANCHIA; OPISTHOBRANCHIATA O*pis`tho*bran"chi*a, O*pis`tho*bran`chi*a"ta, n. pl. Etym: [NL., from Gr. (Zoöl.)

Defn: A division of gastropod Mollusca, in which the breathing organs are usually situated behind the heart. It includes the tectibranchs and nudibranchs.

OPISTHOBRANCHIATE O*pis`tho*bran"chi*ate, a. (Zoöl.)

Defn: Of or pertaining to the Opisthobranchiata. -- n.

Defn: One of the Opisthobranchiata.

OPISTHOCOELIAN; OPISTHOCOELOUS O*pis`tho*coe"li*an, O*pis`tho*coe"lous, a. Etym: [Gr. (Anat.)

Defn: Concave behind; -- applied especially to vertebræ in which the anterior end of the centrum is convex and the posterior concave.

OPISTHODOME O*pis"tho*dome, n. Etym: [L. opisthodomus, Gr. do`mos house: cf. F. opisthodome.] (Arch.)

Defn: A back chamber; especially, that part of the naos, or cella, farthest from the main entrance, sometimes having an entrance of its own, and often used as a treasury.

OPISTHOGLYPHA O*pis`tho*glyph"a, n. pl. Etym: [NL., from Gr. (Zoöl.)

Defn: A division of serpents which have some of the posterior maxillary teeth grooved for fangs.

OPISTHOGRAPHY Op`is*thog"ra*phy, n. Etym: [Gr. -graphy.]

Defn: A writing upon the back of anything, as upon the back of a leaf or sheet already written upon on one side. [R.] Scudamore.

OPISTHOMI Op`is*tho"mi, n. pl. Etym: [NL., fr. Gr. (Zoöl.)

Defn: An order of eellike fishes having the scapular arch attached to the vertebræ, but not connected with the skull.

OPISTHOPULMONATE O*pis`tho*pul"mo*nate, a.Etym: [Gr. pulmonate.] (Zoöl.)

Defn: Having the pulmonary sac situated posteriorly; -- said of certain air-breathing Mollusca.

OPISTHOTIC Op`is*thot"ic, n. Etym: [Gr. (Anat.)

Defn: The inferior and posterior of the three elements forming the periotic bone.

OPISTHOTONOS Op`is*thot"o*nos, n. Etym: [NL., from Gr. (Med.)

Defn: A tetanic spasm in which the body is bent backwards and stiffened.

OPITULATION O*pit`u*la"tion, n. Etym: [L. opitulatio, fr. opitulari to bring help.]

Defn: The act of helping or aiding; help. [Obs.] Bailey.

OPIUM O"pi*um, n. Etym: [L., fr. Gr. (Chem.)

Defn: The inspissated juice of the Papaver somniferum, or white poppy.

Note: Opium is obtained from incisions made in the capsules of the plant, and the best flows from the first incision. It is imported into Europe and America chiefly from the Levant, and large quantities are sent to China from India, Persia, and other countries. It is of a brownish yellow color, has a faint smell, and bitter and acrid taste. It is a stimulant narcotic poison, which may produce hallicinations, profound sleep, or death. It is much used in medicine to soothe pain and inflammation, and is smoked as an intoxicant with baneful effects. Opium joint, a low resort of opium smokers. [Slang]

OPLE TREE O"ple tree`. Etym: [L. opulus a kind of maple tree.]

Defn: The witch-hazel. [Obs.] Ainsworth.

OPOBALSAM; OPOBALSAMUM Op`o*bal"sam, Op`o*bal"sa*mum, n. Etym: [L. opobalsamum, Gr. (Med.)

Defn: The old name of the aromatic resinous juice of the Balsamodendron opobalsamum, now commonly called balm of Gilead. See under Balm.

OPODELDOC Op`o*del"doc, n. Etym: [So called by Paracelsus. The first syllable may be fr. Gr.

1. A kind of plaster, said to have been invented by Mindererus, -- used for external injuries. [Obs.]

2. A saponaceous, camphorated liniment; a solution of soap in alcohol, with the addition of camphor and essential oils; soap liniment.

OPOLCHENIE Op`ol*che"ni*e, n. [Russ., fr. opolchit' to make an army, polk army. Cf. Folk.] (Russia)

Defn: See Army organization, above.

OPOPANAX O*pop"a*nax, n. Etym: [L., fr. Gr. opopanax.]

Defn: The inspissated juice of an umbelliferous plant (the Opoponax Chironum), brought from Turkey and the East Indies in loose granules, or sometimes in larger masses, of a reddish yellow color, with specks of white. It has a strong smell and acrid taste, and was formerly used in medicine as an emmenagogue and antispasmodic. Dunglison.

OPOSSUM O*pos"sum, n. Etym: [Of N. American Indian origin.] (Zoöl.)

Defn: Any American marsupial of the genera Didelphys and Chironectes. The common species of the United States is Didelphys Virginiana.

Note: Several related species are found in South America. The water opossum of Brazil (Chironectes variegatus), which has the hind feet, webbed, is provided with a marsupial pouch and with cheek pouches. It is called also yapock. Opossum mouse. (Zoöl.) See Flying mouse, under Flying. -- Opossum shrimp (Zoöl.), any schizopod crustacean of the genus Mysis and allied genera. See Schizopoda.

OPPIDAN Op"pi*dan, a. Etym: [L. oppidanus, fr. oppidum town.]

Defn: Of or pertaining to a town. Howell.

OPPIDAN Op"pi*dan, n.

1. An inhabitant of a town.

2. A student of Eton College, England, who is not a King's scholar, and who boards in a private family.

OPPIGNERATE Op*pig"ner*ate, v. i. Etym: [L. oppigneratus, p.p. of oppignerare to pawn. See Ob-, and Pignerate.]

Defn: To pledge; to pawn. [Obs.] Bacon.

OPPILATE Op"pi*late, v. t. [imp. & p. p. Oppilated; p. pr. & vb. n. Oppilating.] Etym: [L. oppilatus, p.p. of oppilare to stop up; ob (see Ob-) + pilare to ram down, to thrust.]

Defn: To crowd together; to fill with obstructions; to block up. [Obs.] Cockeram.

OPPILATION Op`pi*la"tion, n. Etym: [L. oppilatio: cf. F. opilation.]

Defn: The act of filling or crowding together; a stopping by redundant matter; obstruction, particularly in the lower intestines. Jer. Taylor.

OPPILATIVE Op`pi*la*tive, a. Etym: [Cf. F. opilatif. See Oppilate.]

Defn: Obstructive. [Obs.] Sherwood.

OPPLETE; OPPLETED Op*plete", Op*plet"ed, a. Etym: [L. oppletus, p.p. of opplere to fill up; ob (see Ob-) + plere to fill.]

Defn: Filled; crowded. [Obs.] Johnson.

OPPLETION Op*ple"tion, n.

Defn: The act of filling up, or the state of being filled up; fullness. [Obs.]

OPPONE Op*pone", v. t. Etym: [L. opponere. See Opponent.]

Defn: To oppose. [Obs.] B. Jonson.

OPPONENCY Op*po"nen*cy, n.

Defn: The act of opening an academical disputation; the proposition of objections to a tenet, as an exercise for a degree. [Eng.] Todd.

OPPONENT Op*po"nent, a. Etym: [L. opponens, -entis, p.pr. of opponere to set or place against, to oppose; ob (see Ob-) + ponere to place. See Position.]

Defn: Situated in front; opposite; hence, opposing; adverse; antagonistic. Pope.

OPPONENT Op*po"nent, n.

1. One who opposes; an adversary; an antagonist; a foe. Macaulay.

2. One who opposes in a disputation, argument, or other verbal controversy; specifically, one who attacks some theirs or proposition, in distinction from the respondent, or defendant, who maintains it. How becomingly does Philopolis exercise his office, and seasonably commit the opponent with the respondent, like a long-practiced moderator! Dr. H. More.

Syn. -- Antagonist; opposer; foe. See Adversary.

OPPORTUNE Op`por*tune", a. Etym: [F. opporiun, L. opportunus, lit., at or before the port; ob (see Ob-) + a derivative of portus port, harbor. See Port harbor.]

Defn: Convenient; ready; hence, seasonable; timely. Milton. This is most opportune to our need. Shak. -- Op`por*tune"ly, adv. -- Op`por*tune"ness, n.

OPPORTUNE Op`por*tune", v. t.

Defn: To suit. [Obs.] Dr. Clerke(1637).

OPPORTUNISM Op`por*tun"ism, n. Etym: [Cf. F. opportunisme.]

Defn: The art or practice of taking advantage of opportunities or circumstances, or of seeking immediate advantage with little regard for ultimate consequences. [Recent]

OPPORTUNIST Op`por*tun"ist, n. Etym: [Cf. F. opportuniste.]

Defn: One who advocates or practices opportunism. [Recent]

OPPORTUNITY Op`por*tu"ni*ty, n.; pl. Opportunities. Etym: [F. opportunité, L. opportunitas. See Opportune.]

1. Fit or convenient time; a time or place favorable for executing a purpose; a suitable combination of conditions; suitable occasion; chance. A wise man will make more opportunities than he finds. Bacon.

2. Convenience of situation; fitness. [Obs.] Hull, a town of great strength and opportunity, both to sea and land affairs. Milton.

3. Importunity; earnestness. [Obs.] Jer. Taylor.

Syn. -- Occasion; convenience; occurrence. -- Opportunity, Occasion. An occasion is that which falls in our way, or presents itself in the course of events; an opportunity is a convenience or fitness of time, place, etc., for the doing of a thing. Hence, occasions often make opportunities. The occasion of sickness may give opportunity for reflection.

OPPOSABILITY Op*pos`a*bil"i*ty, n.

Defn: The condition or quality of being opposable. In no savage have I ever seen the slightest approach to opposability of the great toe, which is the essential distinguishing feature of apes. A. R. Wallace.

OPPOSABLE Op*pos"a*ble, a.

1. Capable of being opposed or resisted.

2. Capable of being placed opposite something else; as, the thumb is opposable to the forefinger.

OPPOSAL Op*pos"al, n.

Defn: Opposition. [R.] Sir T. Herbert.

OPPOSE Op*pose", v. t. [imp. & p. p. Opposed; p. pr. & vb. n. Opposing.] Etym: [F. opposer. See Ob-, Pose, and cf.2d Appose, Puzzle, n. Cf.L. opponere, oppositum.]

1. To place in front of, or over against; to set opposite; to exhibit. Her grace sat down . . . In a rich chair of state; opposing freely The beauty of her person to the people. Shak.

2. To put in opposition, with a view to counterbalance or countervail; to set against; to offer antagonistically. I may . . . oppose my single opinion to his. Locke.

3. To resist or antagonize by physical means, or by arguments, etc.; to contend against; to confront; to resist; to withstand; as, to oppose the king in battle; to oppose a bill in Congress.

4. To compete with; to strive against; as, to oppose a rival for a prize. I am . . . too weak To oppose your cunning. Shak.

Syn. -- To combat; withstand; contradict; deny; gainsay; oppugn; contravene; check; obstruct.

OPPOSE Op*pose", v. i.

1. To be set opposite. Shak.

2. To act adversely or in opposition; -- with against or to; as, a servant opposed against the act. [Obs.] Shak.

3. To make objection or opposition in controversy.

OPPOSELESS Op*pose"less, a.

Defn: Not to be effectually opposed; irresistible. [Obs.] "Your great opposeless wills." Shak.

OPPOSER Op*pos"er, n.

Defn: One who opposes; an opponent; an antagonist; an adversary.

OPPOSITE Op"po*site, a. Etym: [F., fr. L. oppositus, p. p. of opponere. See Opponent.]

1. Placed over against; standing or situated over against or in front; facing; -- often with to; as, a house opposite to the Exchange.

2. Applied to the other of two things which are entirely different; other; as, the opposite sex; the opposite extreme.

3. Extremely different; inconsistent; contrary; repugnant; antagonistic. Novels, by which the reader is misled into another sort of pieasure opposite to that which is designed in an epic poem. Dryden. Particles of speech have divers, and sometimes almost opposite, significations. Locke.

4. (Bot.) (a) Set over against each other, but separated by the whole diameter of the stem, as two leaves at the same node. (b) Placed directly in front of another part or organ, as a stamen which stands before a petal.

OPPOSITE Op"po*site, n.

1. One who opposes; an opponent; an antagonist. [Obs.] The opposites of this day's strife. Shak.

2. That which is opposed or contrary; as, sweetness and its opposite. The virtuous man meets with more opposites and opponents than any other. Landor.

OPPOSITELY Op"po*site*ly, adv.

Defn: In a situation to face each other; in an opposite manner or direction; adversely. Winds from all quarters oppositely blow. May.

OPPOSITENESS Op"po*site*ness, n.

Defn: The quality or state of being opposite.

OPPOSITIFOLIOUS Op*pos`i*ti*fo"li*ous, a. Etym: [See Opposite, Folious.] (Bot.)

Defn: Placed at the same node with a leaf, but separated from it by the whole diameter of the stem; as, an oppositifolious peduncle.

OPPOSITION Op`po*si"tion, n. Etym: [F., fr. L. oppositio. See Opposite.]

1. The act of opposing; an attempt to check, restrain, or defeat; resistance. The counterpoise of so great an opposition. Shak. Virtue which breaks through all opposition. Milton.

2. The state of being placed over against; situation so as to front something else. Milton.

3. Repugnance; contrariety of sentiment, interest, or purpose; antipathy. Shak.

4. That which opposes; an obstacle; specifically, the aggregate of persons or things opposing; hence, in politics and parliamentary practice, the party opposed to the party in power.

5. (Astron.)

Defn: The situation of a heavenly body with respect to another when in the part of the heavens directly opposite to it; especially, the position of a planet or satellite when its longitude differs from that of the sun 180º; -- signified by the symbol as, .

6. (Logic)

Defn: The relation between two propositions when, having the same subject and predicate, they differ in quantity, or in quality, or in both; or between two propositions which have the same matter but a different form.

OPPOSITIONIST Op`po*si"tion*ist, n.

Defn: One who belongs to the opposition party. Praed.

OPPOSITIPETALOUS Op*pos`i*ti*pet"al*ous, a. Etym: [See Opposite, and Petal.] (Bot.)

Defn: Placed in front of a petal.

OPPOSITISEPALOUS Op*pos`i*ti*sep"al*ous, a. Etym: [See Opposite, and Sepal.] (Bot.)

Defn: Placed in front of a sepal.

OPPOSITIVE Op*pos`i*tive, a. Etym: [Cf. F. oppositif. See Opposite.]