Oc"tave (?), a. Consisting of eight; eight. Dryden.
Oc*ta"vo (?), n.;pl. Octavos (#). [L. 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°.
Oc*ta"vo, a. Having eight leaves to a sheet; as, an octavo form, book,
leaf, size, etc.
Oc"tene (?), n. [See Octo-.] (Chem.) Same as Octylene.
Oc*ten"ni*al (?), a. [L. 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, adv.
Oc*tet" (?), n. [From L. octo eight, like E. duet, fr.L. duo. See
Octave.] (Mus.) A composition for eight parts, usually for eight solo
instruments or voices.
Oc"tic (?), a. [Octo- + - ic.] (Math.) Of the eighth degree or order.
-- n. (Alg.) A quantic of the eighth degree.