Fossa
Pronunciation : Fos"sa
Part of Speech : n.;
Etymology : [L., a ditch. See Fosse.] (Anat.)
Definition : Defn: A pit, groove, cavity, or depression, of greater or less depth; as, the temporal fossa on the side of the skull; the nasal foss? containing the nostrils in most birds.
pl. Foss?.
Source : Webster's Unabridged Dictionary, 1913