butternut Meaning, Definition & Usage

  1. noun North American walnut tree having light-brown wood and edible nuts; source of a light-brown dye
    butternut tree; Juglans cinerea; white walnut.
  2. noun oily egg-shaped nut of an American tree of the walnut family

WordNet

But"ter*nut` noun
Definitions
  1. (Bot.) An American tree (Juglans cinerea) of the Walnut family, and its edible fruit; -- so called from the oil contained in the latter. Sometimes called oil nut and white walnut.
  2. (Bot.) The nut of the Caryocar butyrosum and C. nuciferum, of S. America; -- called also Souari nut.

Webster 1913