1) Black hickory 2) Brown hickory 3) Carya glabra 4) Comestible vegetable 5) Comestible root vegetable 6) Comestible root veg 7) Comestible veg 8) Culinary vegetable 9) Edible root 10) Edible vegetable 11) Edible root vegetable 12) Edible tuber 13) Edible root veg 14) Edible veg 15) Edible veggie 16) Food for a herbivore 
• (n.) See Groundnut (d). • (n.) The bitter-flavored nut of a species of hickory (Carya glabra, / porcina); also, the tree itself.
Pig'nut noun (Botany) (a) See Groundnut (d) . (b) The bitter- flavored nut of a species of hickory ( Carya glabra, or porcina ); also, the tree itself. 
[n] - an American hickory tree having bitter nuts
pignut hickory noun an American hickory tree having bitter nuts