semilunar valve vs heart valve

semilunar valve and heart valve both are nouns.

Word	Noun	Adjective	Verb	Adverb
semilunar valve	Yes	No	No	No
heart valve	Yes	No	No	No

As nouns, heart valve is a hypernym of semilunar valve; that is, heart valve is a word with a broader meaning than semilunar valve:

semilunar valve: a heart valve with cusps shaped like half-moons; prevents blood from flowing back into the heart
heart valve: a valve to control one-way flow of blood

Other hypernyms of semilunar valve include cardiac valve.

semilunar valve (noun)	heart valve (noun)
a heart valve with cusps shaped like half-moons; prevents blood from flowing back into the heart	an implant that replaces a natural cardiac valve
	a valve to control one-way flow of blood