Ochery adjective Ocherous. [ Written also ochrey , ochry .]

Ochimy noun [ Obsolete] See Occamy .

Ochlesis noun [ New Latin , from Greek ... disturbance, from ... crowd, mob.] (Medicine) A general morbid condition induced by the crowding together of many persons, esp. sick persons, under one roof. G. Gregory.

Ochlocracy noun [ Greek ...; ... the populace, multitude + ... to be strong, to rule, ... strength: confer French ochlocratie .] A form of government by the multitude; a mobocracy. Hare.

Ochlocratic, Ochlocratical adjective Of or pertaining to ochlocracy; having the form or character of an ochlocracy; mobocratic.

-- Och`lo*crat"ic*al*ly , adverb

Ochraceous adjective Ocherous.

Ochre noun (Min.) See Ocher .

Ochrea noun ; plural Ochreæe . [ Latin ]
1. (Antiq.) A greave or legging.

2. (Botany) A kind of sheath formed by two stipules united round a stem.

Ochreate, Ochreated adjective
1. Wearing or furnished with an ochrea or legging; wearing boots; booted.

A scholar undertook . . . to address himself ochreated unto the vice chancellor.

Fuller.

2. (Botany) Provided with ochrea, or sheathformed stipules, as the rhubarb, yellow dock, and knotgrass.

Ochreous adjective See Ocherous .

Ochrey adjective See Ochery .

Ochroleucous adjective [ Greek ... ocher + ... white.] Yellowish white; having a faint tint of dingy yellow. Gray.

Ochry adjective See Ochery .

Ochymy noun [ Obsolete] See Occamy .

Ocra noun (Botany) See Okra .

Ocrea noun [ Latin ] See Ochrea .

Ocreate, Ocreated adjective [ See Ochrea .] Same as Ochreate , Ochreated .

Octa- A prefix meaning eight . See Octo- .

Octachord noun [ Greek ... with eight strings; ... (for ... eight) + ... string, chord: confer French octacorde .] (Mus.) An instrument of eight strings; a system of eight tones. [ Also written octochord .]

Octad noun [ Greek ..., ..., the number eight.] (Chemistry) An atom or radical which has a valence of eight, or is octavalent.

Octaedral adjective See Octahedral .

Octaemeron noun [ New Latin , from Greek ..., neut. of ... of the eighth day.] (Eccl.) A fast of eight days before a great festival. Shipley.

Octagon noun [ Greek ... eight- cornered; ... (for ... eight) + ... an angle: confer French cctogone .]
1. (Geom.) A plane figure of eight sides and eight angles.

2. Any structure (as a fortification) or place with eight sides or angles.

Regular octagon , one in which the sides are all equal, and the angles also are all equal.

Octagonal adjective Having eight sides and eight angles.

Octagynous adjective [ Octa- + Greek ... wife.] (Botany) Having eight pistils or styles; octogynous.

Octahedral adjective [ See Octahedron .] Having eight faces or sides; of, pertaining to, or formed in, octahedrons; as, octahedral cleavage.

Octahedral borax (Chemistry) , borax obtained from a saturated solution in octahedral crystals, which contain five molecules of water of crystallization; distinguished from common or prismatic borax . -- Octahedral iron ore (Min.) , magnetite.

Octahedrite noun (Min.) Titanium dioxide occurring in acute octahedral crystals.

Octahedron noun [ Greek ..., from ... eight-side; ... (for ... eight) + ... seat, base, from ... to sit.] (Geom.) A solid bounded by eight faces. The regular octahedron is contained by eight equal equilateral triangles.

Octamerous adjective [ Octa- + Greek ... part.] (Biol.) Having the parts in eights; as, an octamerous flower; octamerous mesenteries in polyps.

Octameter noun [ Confer L. octameter in eight feet. See Octa- , and meter .] (Pros.) A verse containing eight feet; as, --

Deep\'b6 in

Octander noun One of the Octandria.

Octandria noun plural [ New Latin , from Greek ... (for ... eight) + ..., ..., male, man.] (Botany) A Linnæan class of plants, in which the flowers have eight stamens not united to one another or to the pistil.

Octandrian, Octandrous adjective (Botany) Of or pertaining to the Octandria; having eight distinct stamens.

Octane noun [ See Octa- ] . (Chemistry) Any one of a group of metametric hydrocarcons (C ₈ H ₁₈ ) of the methane series. The most important is a colorless, volatile, inflammable liquid, found in petroleum, and a constituent of benzene or ligroin.

Octangular adjective [ Latin octangulus eight-cornered; octo eight + angulus angle.] Having eight angles; eight-angled. -- Oc*tan"gu*lar*ness , noun

Octant noun [ Latin octans , - antis . from octo eight. See Octave .]
1. (Geom.) The eighth part of a circle; an arc of 45 degrees.

2. (Astron. & Astrol.) The position or aspect of a heavenly body, as the moon or a planet, when half way between conjunction, or opposition, and quadrature, or distant from another body 45 degrees.

3. An instrument for measuring angles (generally called a quadrant ), having an arc which measures up to 9O°, but being itself the eighth part of a circle. Confer Sextant .

4. (Math. & Crystallog.) One of the eight parts into which a space is divided by three coördinate planes.

Octapla noun ; etymol. plural , but syntactically sing. [ New Latin , from Greek ... (for ... eight) + -pla , as in English hexapla ; confer Greek ... eightfold.] A portion of the Old Testament prepared by Origen in the 3d century, containing the Hebrew text and seven Greek versions of it, arranged in eight parallel columns.

Octaroon noun See Octoroon .

Octastyle adjective See Octostyle .

Octateuch noun [ Latin octateuchus , Greek ....] A collection of eight books; especially, the first eight books of the Old Testament. [ R.]

Octavalent adjective [ Octa- + Latin valens , present participle See Valence .] (Chemistry) Having a valence of eight; capable of being combined with, exchanged for, or compared with, eight atoms of hydrogen; -- said of certain atoms or radicals.

Octave noun [ French, from Latin octava an eighth, from octavus eighth, from octo eight. See Eight , and confer Octavo , Utas .]
1. The eighth day after a church festival, the festival day being included; also, the week following a church festival. "The octaves of Easter." Jer. Taylor.

2. (Mus.) (a) The eighth tone in the scale; the interval between one and eight of the scale, or any interval of equal length; an interval of five tones and two semitones. (b) The whole diatonic scale itself.

» The ratio of a musical tone to its octave above is 1:2 as regards the number of vibrations producing the tones.

3. (Poet.) The first two stanzas of a sonnet, consisting of four verses each; a stanza of eight lines.

With mournful melody it continued this octave .

Sir P. Sidney.

Double octave . (Mus.) See under Double . -- Octave flute (Mus.) , a small flute, the tones of which range an octave higher than those of the German or ordinary flute; -- called also piccolo . See Piccolo .

4. A small cask of wine, the eighth part of a pipe.

Octave adjective Consisting of eight; eight. Dryden.

Octavo noun ; plural Octavos . [ Latin in octavo ; in in + octavo , abl. of octavus . See Octave .] A book composed of sheets each of which is folded into eight leaves; hence, indicating more or less definitely a size of book so made; -- usually written 8vo or 8°.

Octavo adjective Having eight leaves to a sheet; as, an octavo form, book, leaf, size, etc.

Octene noun [ See Octo- .] (Chemistry) Same as Octylene .

Octennial adjective [ Latin octennium a period of eight years; octo eight + annus year.] Happening every eighth year; also, lasting a period of eight years. Johnson. -- Oc*ten"ni*al*ly , adverb

Octet noun [ From Latin octo eight, like English duet , from Latin duo . See Octave .] (Mus.) A composition for eight parts, usually for eight solo instruments or voices.

Octic adjective [ Octo- + - ic .] (Math.) Of the eighth degree or order. -- noun (Alg.) A quantic of the eighth degree.

Octile noun [ Confer French octil , adjective See Octant .] Same as Octant , 2. [ R.]