Definition of jack bean
: a bushy annual tropical American legume (Canavalia ensiformis) grown especially for forage
First Known Use of jack bean
Medical Definition of jack bean
1: an annual tropical American plant of the genus Canavalia; especially : a plant (C. ensiformis) having long pods with white seeds and grown especially for forage
2: the seed of the jack bean that is a source of canavalin and urease
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