oyster mushroom vs oyster agaric

oyster mushroom and oyster agaric both are nouns.

Word	Noun	Adjective	Verb	Adverb
oyster mushroom	Yes	No	No	No
oyster agaric	Yes	No	No	No

As nouns, oyster mushroom and oyster agaric are synonyms defined as:

oyster mushroom and oyster agaric: edible agaric with a soft greyish cap growing in shelving masses on dead wood

Other synonyms of oyster mushroom include oyster fungus, Pleurotus ostreatus.

oyster mushroom (noun)	oyster agaric (noun)
edible agaric with a soft greyish cap growing in shelving masses on dead wood	edible agaric with a soft greyish cap growing in shelving masses on dead wood