English
exolabial
From exo- + labial.
Proto-Indo-European *h₁eǵʰs ‘out of’
Proto-Hellenic *eks
Ancient Greek ἐκ ‘Out of, from’
Ancient Greek ἔξω ‘outer’
English exo-
Proto-Indo-European *leb- ‘to hang down loosely’
Proto-Indo-European *l̥b-yóm
Proto-Italic *labjom
Latin labium ‘a lip’
Medieval Latin labiālis ‘of or pertaining to the lips’
English labial
Today it means
adj Of a form of vowel rounding, in which the corners of the mouth are drawn slightly together and the lips may be compressed horizontally, but the lips do not protrude and only their outer surface is exposed.
Language periods are conventional ranges, not dates for this word.
Etymograph / exolabial