Source : Webster's Revised Unabridged Dictionary (1913)

Mediostapedial \Me`di*o*sta*pe"di*al\, a. [L. medius middle + E.
   stapedial.] (Anat.)
   Pertaining to that part of the columella of the ear which, in
   some animals, connects the stapes with the other parts of the
   columella. -- n. The mediostapedial part of the columella.