a. and sb. [ad. med.L. labiālis, f. labi-um lip. Cf. F. labial (1690 in Furetière).]
A. adj.
1. Of or pertaining to the lips.
1650. Bulwer, Anthropomet., xi. 107. Lip-Gallantry, or certain labial Fashions invented by diverse Nations.
1837. Marryat, Dog-fiend, xix. The olfactory examination was favourable, so he put his mouth to it—the labial essay still more so.
1848. Clough, Amours de Voy., ii. 157. The labial muscles that swelled with Vehement evolution of yesterday Marseillaises.
1867. Jean Ingelow, Lily & Lute, ii. 108. More than I can make you view, With my paintings labial.
1867. A. J. Ellis, E. E. Pronunc., I. iii. § 3. 161. The volume of the mouth is divided into two bent tubes of which the first may be termed the lingual passage as its front extremity is formed by the tongue, and the second, the labial passage.
b. spec. in Anat., Zool., etc. Pertaining to a lip, lip-like part, or LABIUM; having the character or functions of a lip.
1656. Blount, Glossogr., s.v. Vein, Labial veins, the lip veines, whereof there are two on each inner side, both of the upper and under lip.
1722. Quincy, Lex. Physico-Med. (ed. 2), 227. Labial Glands.
1826. Kirby & Sp., Entomol., III. 356. Palpi Labiales (the Labial Feelers).
1851–6. Woodward, Mollusca, 211. The lips and labial tentacles of the ordinary bivalves.
1879. T. Bryant, Pract. Surg., II. 230. Labial cysts are very common, and are usually met with on the inner side of the labia.
1881. Mivart, Cat, 27. The membrane lining the mouth abounds in small glands, those within the cheeks and lips being termed buccal and labial respectively.
c. Labial pipe: an organ-pipe furnished with lips, a flue-pipe.
1852. Seidel, Organ, 21. An organ … which contained the following labial or languet registers.
1863. Tyndall, Heat, viii. App. 280. The flame is also affected by various D’s of an adjustable labial pipe.
1876. Hiles, Catech. Organ, iv. (1878), 23. Flue-pipes are also called Labial, or lip-pipes.
2. Phonetics. The distinctive epithet of those sounds that require complete or partial closure of the lips for their formation, as the consonants p, b, m, f, v, w, and the ‘rounded’ vowels.
1594. T. B., La Primaud. Fr. Acad., II. 87. The Hebrewes name their letters, some gutturall…; others dentall…; & so they call others, labiall, that is letters of the lips.
c. 1620. A. Hume, Brit. Tongue, I. vii. I beginning to lay my grundes of labial, dental, and guttural soundes and symboles. Ibid. A labial letter can not symboliz a guttural syllab.
1668. Wilkins, Real Char., III. xiv. 379. The Vowels, as they are distinguished into Labial; being framed by an emission of the Breath through the Lips [etc.].
1865. Tylor, Hist. Man., iv. 73. Words containing labial and dental letters.
B. sb.
1. A labial sound.
1668. Wilkins, Real Char., III. xiv. 380. The Labials are represented by two curve Figures for the Lips.
a. 1709. W. Baxter, Lett., in Gloss. Antiq. Rom. (1731), 409. The third Sort are Labials formed by the Lips alone.
1849–50. Thackeray, Pendennis, xlvi. You have but the same four letters to describe the salute which … you bestow on the sacred cheek of your mistress—but the same four letters and not one of them a labial.
1864. Max Müller, Sci. Lang., Ser. II. iv. 162. It is a fact … that the Mohawks … have no p, b, m, f, v, w—no labials of any kind.
2. A labial part or organ, e.g., one of the plates or scales that border the mouth of a fish or reptile, one of the labial palpi of insects.
1884. W. K. Parker, Mammalian Descent (1885), ii. 45–6. The finished labials (lip-cartilages) of the types just referred to.
Hence Labially adv., with a labial sound or utterance.
1798. H. T. Colebrooke, trans. Dig. Hindu Law (1801), I. xxvii. Sometimes pronounced gutturally, sometimes labially.
