adj. & n.
--adj.
1. a of the lips. b Zool. of, like, or serving as a lip, a liplike part, or a labium.
2 Dentistry designating the surface of a tooth adjacent to the lips.
3 Phonet. (of a sound) requiring partial or complete closure of the lips (e.g. p, b, f, v, m, w; and vowels in which lips are rounded, e.g. oo in m oon).
--n. Phonet. a labial sound.
Phrases and idioms:
labial pipe Mus. an organ-pipe having lips; a flue-pipe.
Derivatives:
labialism n. labialize v.tr. (also -ise). labially adv.
Etymology: med.L labialis f. L labia lips