remains vs cadaver

remains and cadaver both are nouns.

Word	Noun	Adjective	Verb	Adverb
remains	Yes	No	No	No
cadaver	Yes	No	No	No

As nouns, remains and cadaver are synonyms defined as:

Other synonyms of remains include clay, corpse, stiff.

remains (noun)	cadaver (noun)
the dead body of a human being	the dead body of a human being
any object that is left unused or still extant
a relic that has been excavated from the soil