Greek deity vs Poseidon

Greek deity and Poseidon both are nouns.

Word	Noun	Adjective	Verb	Adverb
Greek deity	Yes	No	No	No
Poseidon	Yes	No	No	No

Greek deity (noun)	Poseidon (noun)
a deity worshipped by the ancient Greeks	(Greek mythology) the god of the sea and earthquakes in ancient mythology; brother of Zeus and Hades and Hera; identified with Roman Neptune