horse bean vs broad-bean plant

horse bean and broad-bean plant both are nouns.

Word	Noun	Adjective	Verb	Adverb
horse bean	Yes	No	No	No
broad-bean plant	Yes	No	No	No

horse bean (noun)	broad-bean plant (noun)
a bean plant cultivated for use animal fodder	Old World upright plant grown especially for its large flat edible seeds but also as fodder