groundnut

n. (Bot.) (a) The fruit of the Arachis hypogæa (native country uncertain); the peanut; the earthnut. (b) A leguminous, twining plant (Apios tuberosa), producing clusters of dark purple flowers and having a root tuberous and pleasant to the taste. (c) The dwarf ginseng (Aralia trifolia). [ U. S. ] Gray. (d) A European plant of the genus Bunium (B. flexuosum), having an edible root of a globular shape and sweet, aromatic taste; -- called also earthnut, earth chestnut, hawknut, and pignut. [ 1913 Webster ]