Word Study
Fossa
CIDE DICTIONARY
Fossa, n. [L., a ditch. See Fosse.].
A pit, groove, cavity, or depression, of greater or less depth; as, the temporal fossa on the side of the skull; the nasal fossæ containing the nostrils in most birds. [1913 Webster]
OXFORD DICTIONARY
Fossa, n. (pl. fossae) Anat. a shallow depression or cavity.
Etymology
L, = ditch, fem. past part. of fodere dig
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