/tong"keuh/
1. the fragrant, black almond-shaped seed of a tall tree belonging to the genus Dipteryx (or Coumarouna ), of the legume family, esp. D. odorata, of tropical South America, used in perfumes, as a source of coumarin, and as a substitute for vanilla.
2. the tree itself.
[ 1790-1800; tonka prob. tõka ]