mesethmoid

from The Collaborative International Dictionary of English v.0.48

Mesethmoid \Mes*eth"moid\, a. [Mes- + ethmoid.] (Anat.)
   Of or pertaining to the middle of the ethmoid region or
   ethmoid bone. -- n. (Anat.) The median vertical plate, or
   median element, of the ethmoid bone.
   [1913 Webster]