What is "helicotrema"

Helicotrema \Hel`i*co"tre"ma\, n. [NL., fr. Gr. "e`lix, "e`likos, a helix + ? a hole.] (Anat.) The opening by which the two scal[ae] communicate at the top of the cochlea of the ear.

n. (context anatomy English) The opening by which the two scalae communicate at the top of the cochlea of the ear.

The helicotrema (from Greek ἕλιξ meaning coil and τρη̂μα meaning hole) is the part of the cochlear labyrinth where the scala tympani and the scala vestibuli meet. It is the main component of the cochlear apex. The hair cells near this area best detect low frequency sounds.