departed vs somebody

departed and somebody both are nouns.

Word	Noun	Adjective	Verb	Adverb
departed	Yes	Yes	No	No
somebody	Yes	No	No	No

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

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

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

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

departed (adjective)	somebody (adjective)
dead
well in the past; former