wild pea vs leguminous plant

wild pea and leguminous plant both are nouns.

Word	Noun	Adjective	Verb	Adverb
wild pea	Yes	No	No	No
leguminous plant	Yes	No	No	No

As nouns, leguminous plant is a hypernym of wild pea; that is, leguminous plant is a word with a broader meaning than wild pea:

wild pea: any of various plants of the family Leguminosae that usually grow like vines
leguminous plant: an erect or climbing bean or pea plant of the family Leguminosae

Other hypernyms of wild pea include legume.

wild pea (noun)	leguminous plant (noun)
any of various plants of the family Leguminosae that usually grow like vines	an erect or climbing bean or pea plant of the family Leguminosae