legume vs leguminous plant

legume and leguminous plant both are nouns.

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

As nouns, legume and leguminous plant are synonyms defined as:

legume and leguminous plant: an erect or climbing bean or pea plant of the family Leguminosae

legume (noun)	leguminous plant (noun)
the seedpod of a leguminous plant (such as peas or beans or lentils)	an erect or climbing bean or pea plant of the family Leguminosae
an erect or climbing bean or pea plant of the family Leguminosae
the fruit or seed of any of various bean or pea plants consisting of a case that splits along both sides when ripe and having the seeds attach to one side of the case