Fossa
in zoölogy, a term applied to certain depressions on the external the ext external surface, generally the seat of cutaneous glands, as the lachrymal fossæ in deer and antelopes.
FOSSIL In anatomy (1) In the singular, a groove. There are in the ear a fossa of the helix, which is a groove called also fossa innominata or scaphoidea, and a fossa of the antihelix, which is a somewhat triangular depression, called also fossa triangularis or ovalis. There are also a fossa of the heart, one of the gall bladder, etc. There are also a canine, a corodoid, a digastric, a digital and many other fossa. (2) In the plural, grooves. There are nasal fossæ, superior and inferior occipital, etc.