pea vs leguminous plant

pea and leguminous plant both are nouns.

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

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

pea: a leguminous plant of the genus Pisum with small white flowers and long green pods containing edible green seeds
leguminous plant: an erect or climbing bean or pea plant of the family Leguminosae

Other hypernyms of pea include legume.

pea (noun)	leguminous plant (noun)
seed of a pea plant used for food	an erect or climbing bean or pea plant of the family Leguminosae
a leguminous plant of the genus Pisum with small white flowers and long green pods containing edible green seeds
the fruit or seed of a pea plant