deceased person vs somebody

deceased person and somebody both are nouns.

Word	Noun	Adjective	Verb	Adverb
deceased person	Yes	No	No	No
somebody	Yes	No	No	No

As nouns, somebody is a hypernym of deceased person; that is, somebody is a word with a broader meaning than deceased person:

deceased person: someone who is no longer alive
somebody: a human being; person, singular, assertive existential pronoun; pronoun, person, singular; quantifier: assertive existential

Other hypernyms of deceased person include individual, mortal, person, someone, soul.

deceased person (noun)	somebody (noun)
someone who is no longer alive	a human being; person, singular, assertive existential pronoun; pronoun, person, singular; quantifier: assertive existential