creeping bent vs bent grass

creeping bent and bent grass both are nouns.

Word	Noun	Adjective	Verb	Adverb
creeping bent	Yes	No	No	No
bent grass	Yes	No	No	No

As nouns, bent grass is a hypernym of creeping bent; that is, bent grass is a word with a broader meaning than creeping bent:

creeping bent: common pasture or lawn grass spread by long runners
bent grass: grass for pastures and lawns especially bowling and putting greens

Other hypernyms of creeping bent include bent-grass, bent.

creeping bent (noun)	bent grass (noun)
common pasture or lawn grass spread by long runners	grass for pastures and lawns especially bowling and putting greens