field bindweed vs bindweed

field bindweed and bindweed both are nouns.

Word	Noun	Adjective	Verb	Adverb
field bindweed	Yes	No	No	No
bindweed	Yes	No	No	No

As nouns, bindweed is a hypernym of field bindweed; that is, bindweed is a word with a broader meaning than field bindweed:

field bindweed: weakly climbing European perennial with white or pink flowers; naturalized in North America and an invasive weed
bindweed: any of several vines of the genera Convolvulus and Calystegia having a twining habit

field bindweed (noun)	bindweed (noun)
weakly climbing European perennial with white or pink flowers; naturalized in North America and an invasive weed	any of several vines of the genera Convolvulus and Calystegia having a twining habit