Word Study
tonka bean
CIDE DICTIONARY
tonka bean, [Cf. F. onca, tonka.].
The seed of a leguminous tree (Dipteryx odorata ), native of Guiana. It has a peculiarly agreeable smell, and is employed in the scenting of snuff. Called also tonquin bean . [1913 Webster]
OXFORD DICTIONARY
tonka bean, n. the black fragrant seed of a South American tree, Dipteryx odorata, used in perfumery etc.
Etymology
tonka, its name in Guyana, + BEAN
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