glenoid cavity vs fossa

glenoid cavity and fossa both are nouns.

Word	Noun	Adjective	Verb	Adverb
glenoid cavity	Yes	No	No	No
fossa	Yes	No	No	No

As nouns, fossa is a hypernym of glenoid cavity; that is, fossa is a word with a broader meaning than glenoid cavity:

glenoid cavity: the concavity in the head of the scapula that receives the head of the humerus to form the shoulder joint
fossa: a concavity in a surface (especially an anatomical depression)

Other hypernyms of glenoid cavity include pit.

glenoid cavity (noun)	fossa (noun)
the concavity in the head of the scapula that receives the head of the humerus to form the shoulder joint	largest carnivore of Madagascar; intermediate in some respects between cats and civets
	a concavity in a surface (especially an anatomical depression)