locust tree vs locust

locust tree and locust both are nouns.

Word	Noun	Adjective	Verb	Adverb
locust tree	Yes	No	No	No
locust	Yes	No	No	No

As nouns, locust tree and locust are synonyms defined as:

locust tree and locust: any of various hardwood trees of the family Leguminosae

locust tree (noun)	locust (noun)
any of various hardwood trees of the family Leguminosae	migratory grasshoppers of warm regions having short antennae
	any of various hardwood trees of the family Leguminosae
	hardwood from any of various locust trees