swamp locust vs locust

swamp locust and locust both are nouns.

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

As nouns, locust is a hypernym of swamp locust; that is, locust is a word with a broader meaning than swamp locust:

swamp locust: honey locust of swamps and bottomlands of southern United States having short oval pods; yields dark heavy wood
locust: any of various hardwood trees of the family Leguminosae

Other hypernyms of swamp locust include locust tree.

swamp locust (noun)	locust (noun)
honey locust of swamps and bottomlands of southern United States having short oval pods; yields dark heavy wood	migratory grasshoppers of warm regions having short antennae
	any of various hardwood trees of the family Leguminosae
	hardwood from any of various locust trees