ton·ka bean (tŏngkə)
1. A tropical South American tree (Dipteryx odorata) in the pea family, having pulpy, egg-shaped, one-seeded pods with fragrant seeds containing coumarin.
2. The seed of this tree, formerly widely used as a flavoring for food or tobacco. Extracts from tonka beans have been banned as food additives in the United States.
[Perhaps from Galibi tonka.]
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