cardiac valve vs cusp

cardiac valve and cusp both are nouns.

Word	Noun	Adjective	Verb	Adverb
cardiac valve	Yes	No	No	No
cusp	Yes	No	No	No

cardiac valve (noun)	cusp (noun)
a valve to control one-way flow of blood	point formed by two intersecting arcs (as from the intrados of a Gothic arch)
	small elevation on the grinding surface of a tooth
	a thin triangular flap of a heart valve