Tōn'ka-bēan, n.

n. [Fr. tonca, tonka, tonga.] (Bot.) The fruit of the Coumarouna (Dipterix) odorata, a shrubby plant of Guiana. It has a peculiarly agreeable smell, and is employed in the scenting of snuff. [Written also tonca-bean, tonga-bean, and tonquin-bean.]