1819, in reference to the inner ear part, from vestibule + -ar.
Entries linking to vestibular
vestibule n.
1620s, "a porch," later "antechamber, lobby" (1730), from French vestible, from Latin vestibulum "forecourt, entrance," of unknown origin. In reference to the ear part from 1728.
-ar
word-formation element meaning "pertaining to, of the nature of," from Latin -arem, -aris "of the kind of, belonging to," a secondary form (by dissimilation) of -alis, used after syllables with an -l- (such as insularis for *insulalis, stellaris for *stellalis).