decedent vs deceased person

decedent and deceased person both are nouns.

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

As nouns, decedent and deceased person are synonyms defined as:

Other synonyms of decedent include dead person, dead soul, deceased, departed.

decedent (noun)	deceased person (noun)
someone who is no longer alive	someone who is no longer alive