volcano vs scissure

volcano and scissure both are nouns.

Word	Noun	Adjective	Verb	Adverb
volcano	Yes	No	No	No
scissure	Yes	No	No	No

As nouns, scissure is a hypernym of volcano; that is, scissure is a word with a broader meaning than volcano:

volcano: a fissure in the earth's crust (or in the surface of some other planet) through which molten lava and gases erupt
scissure: a long narrow cleft

Other hypernyms of volcano include cleft, crack, crevice, fissure.

volcano (noun)	scissure (noun)
a mountain formed by volcanic material	a long narrow cleft
a fissure in the earth's crust (or in the surface of some other planet) through which molten lava and gases erupt