Groove of promontory
Sulcus promontorii
Definition
The promontory (promontorium) is a rounded hollow prominence, formed by the projection outward of the first turn of the cochlea; it is placed between the fenestræ, and is furrowed on its surface by small grooves (Groove of promontory), for the lodgement of branches of the tympanic plexus.
References
This definition incorporates text from a public domain edition of Gray's Anatomy (20th U.S. edition of Gray's Anatomy of the Human Body, published in 1918 – from http://www.bartleby.com/107/).