American red plum vs August plum

American red plum and August plum both are nouns.

Word	Noun	Adjective	Verb	Adverb
American red plum	Yes	No	No	No
August plum	Yes	No	No	No

As nouns, American red plum and August plum are synonyms defined as:

American red plum and August plum: wild plum trees of eastern and central North America having red-orange fruit with yellow flesh

Other synonyms of American red plum include goose plum, Prunus americana.

American red plum (noun)	August plum (noun)
wild plum trees of eastern and central North America having red-orange fruit with yellow flesh	wild plum trees of eastern and central North America having red-orange fruit with yellow flesh