horse bean vs Vicia faba

horse bean and Vicia faba both are nouns.

Word	Noun	Adjective	Verb	Adverb
horse bean	Yes	No	No	No
Vicia faba	Yes	No	No	No

horse bean (noun)	Vicia faba (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