rift vs crevice

rift and crevice both are nouns.

Word	Noun	Adjective	Verb	Adverb
rift	Yes	No	No	No
crevice	Yes	No	No	No

As nouns, crevice is a hypernym of rift; that is, crevice is a word with a broader meaning than rift:

Other hypernyms of rift include cleft, crack, fissure, scissure.

rift (noun)	crevice (noun)
a personal or social separation (as between opposing factions)	a long narrow cleft
a narrow fissure in rock	a long narrow depression in a surface
a gap between cloud masses