black-eyed pea vs legume

black-eyed pea and legume both are nouns.

Word	Noun	Adjective	Verb	Adverb
black-eyed pea	Yes	No	No	No
legume	Yes	No	No	No

As nouns, legume is a hypernym of black-eyed pea; that is, legume is a word with a broader meaning than black-eyed pea:

black-eyed pea: eaten fresh as shell beans or dried
legume: the seedpod of a leguminous plant (such as peas or beans or lentils)

As nouns, legume is a hypernym of black-eyed pea; that is, legume is a word with a broader meaning than black-eyed pea:

black-eyed pea: sprawling Old World annual cultivated especially in southern United States for food and forage and green manure
legume: an erect or climbing bean or pea plant of the family Leguminosae

Other hypernyms of black-eyed pea include leguminous plant.

As nouns, legume is a hypernym of black-eyed pea; that is, legume is a word with a broader meaning than black-eyed pea:

black-eyed pea: fruit or seed of the cowpea plant
legume: 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

black-eyed pea (noun)	legume (noun)
eaten fresh as shell beans or dried	the seedpod of a leguminous plant (such as peas or beans or lentils)
sprawling Old World annual cultivated especially in southern United States for food and forage and green manure	an erect or climbing bean or pea plant of the family Leguminosae
fruit or seed of the cowpea plant	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