marsh pea(n = noun.plant) lathyrus palustris - scrambling perennial of damp or marshy areas of Eurasia and North America with purplish flowers;
is a kind of wild pea
is a member of genus lathyrus, lathyrus

angola pea, asparagus pea, australian pea, austrian winter pea, beach pea, bitter pea, black pea, black-eyed pea, blue pea, broad-leaved everlasting pea, burweed marsh elder, bush pea, butterfly pea, cajan pea, caley pea, calnada pea, catjang pea, chaparral pea, chinese pea tree, common flat pea, common pea, coral pea, darling pea, desert pea, earth-nut pea, earthnut pea, edible-pod pea, edible-podded pea, egyptian pea, everlasting pea, field pea, flame pea, flat pea, garden pea, garden pea plant, glory pea, golden pea, goober pea, grass pea, green pea, green pea soup, hairy darling pea, heart pea, heath pea, hoary pea, indian pea, long-billed marsh wren, marrowfat pea, marsh, marsh andromeda, marsh bellflower, marsh buggy, marsh clematis, marsh cress, marsh elder, marsh felwort, marsh fern, marsh gas, marsh gentian, marsh hare, marsh harrier, marsh hawk, marsh hen, marsh horsetail, marsh mallow, marsh marigold, marsh milkweed, marsh orchid, marsh pink, marsh plant, marsh rosemary, marsh st-john's wort, marsh tea, marsh trefoil, marsh wren, meadow pea, narrow-leaved everlasting pea, ngaio marsh, partridge pea, pea, pea bean, pea brained, pea coat, pea crab, pea family, pea flour, pea green, pea jacket, pea plant, pea pod, pea shooter, pea soup, pea tree, pea weevil, perennial pea, perennial salt marsh aster, pigeon pea, poison pea, purple pea, reginald marsh, rough pea, salt marsh, salt marsh mallow, sea pea, sensitive pea, shamrock pea, short-billed marsh wren, siberian pea tree, singletary pea, smooth darling pea, snap pea, snow pea, sturt pea, sturt's desert pea, sugar pea, sugar snap pea, sweet pea, tangier pea, western australia coral pea, wild pea, wild sweet pea, winged pea, yellow pea