What is (a) See Groundnut (d). (b) The bitter-flavored nut of a species of hickory (Carya glabra, or porcina); also, the tree itself called?

pignut — (a) See Groundnut (d). (b) The bitter-flavored nut of a species of hickory (Carya glabra, or porcina); also, the tree itself. (Webster's 1913.)

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