trou-de-loup vs cavity

trou-de-loup and cavity both are nouns.

Word	Noun	Adjective	Verb	Adverb
trou-de-loup	Yes	No	No	No
cavity	Yes	No	No	No

As nouns, cavity is a hypernym of trou-de-loup; that is, cavity is a word with a broader meaning than trou-de-loup:

trou-de-loup: a sloping pit with a stake in the middle used as an obstacle to the enemy
cavity: a sizeable hole (usually in the ground)

Other hypernyms of trou-de-loup include pit.

trou-de-loup (noun)	cavity (noun)
a sloping pit with a stake in the middle used as an obstacle to the enemy	(anatomy) a natural hollow or sinus within the body
	a sizeable hole (usually in the ground)
	soft decayed area in a tooth; progressive decay can lead to the death of a tooth
	space that is surrounded by something