is a specific kind of: legume, leguminous plant.

is a broader term that covers: Caley pea, Lathyrus hirsutus, rough pea, singletary pea, wild winterpea | beach pea, Lathyrus japonicus, Lathyrus maritimus, sea pea | Lathyrus palustris, marsh pea | common vetchling, Lathyrus pratensis, meadow pea, yellow vetchling | Lathyrus splendens, pride of California | Lalthyrus tingitanus, Tangier pea, Tangier peavine.

is a member of: Fabaceae, family Fabaceae, family Leguminosae, legume family, Leguminosae, pea family.