coch·le·a 
(kŏklē-ə, kōklē-ə)
(kŏklē-ə, kōklē-ə)n. pl. coch·le·ae (-lē-ē′, -lē-ī′) also coch·le·as
A spiral-shaped cavity of the inner ear that resembles a snail shell and contains nerve endings essential for hearing.
[Latin, snail shell, from Greek kokhliās, snail, from kokhlos, land snail.]
cochle·ar adj.