beach plum vs wild plum

beach plum and wild plum both are nouns.

Word	Noun	Adjective	Verb	Adverb
beach plum	Yes	No	No	No
wild plum	Yes	No	No	No

As nouns, wild plum is a hypernym of beach plum; that is, wild plum is a word with a broader meaning than beach plum:

beach plum: seacoast shrub of northeastern North America having showy white blossoms and edible purple fruit
wild plum: an uncultivated plum tree or shrub

Other hypernyms of beach plum include wild plum tree.

beach plum (noun)	wild plum (noun)
small dark purple fruit used especially in jams and pies	fruit of the wild plum of southern United States
seacoast shrub of northeastern North America having showy white blossoms and edible purple fruit	an uncultivated plum tree or shrub