Souari nut \Sou*a"ri nut`\ (Bot.) The large edible nutlike seed of a tall tropical American tree (Caryocar nuciferum) of the same natural order with the tea plant; -- also called butternut. [Written also sawarra nut.]

Source: Webster's Revised Unabridged Dictionary (1913)
 

Butternut \But"ter*nut`\, n.

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.

Source: Webster's Revised Unabridged Dictionary (1913)