Root vegetables are plant roots used as vegetables. Other underground plants are often, erroneously, called root vegetables. Root vegetables include both true roots such as tuberous roots and taproots, but exclude non-roots such as tubers, rhizomes, corms, and bulbs. Several types contain both taproot and hypocotyl tissue, and it may be difficult to distinguish the two.
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Noun 1. any of various fleshy edible underground roots or tubers (hypernym) vegetable, veggie (hyponym) potato, white potato, Irish potato, murphy, spud, tater