stress fracture vs fracture

stress fracture and fracture both are nouns.

Word	Noun	Adjective	Verb	Adverb
stress fracture	Yes	No	No	No
fracture	Yes	No	Yes	No

As nouns, fracture is a hypernym of stress fracture; that is, fracture is a word with a broader meaning than stress fracture:

stress fracture: fracture resulting from excessive activity rather than a specific injury
fracture: breaking of hard tissue such as bone

Other hypernyms of stress fracture include break.

stress fracture (noun)	fracture (noun)
fracture resulting from excessive activity rather than a specific injury	the act of cracking something
	(geology) a crack in the earth's crust resulting from the displacement of one side with respect to the other
	breaking of hard tissue such as bone