the seed of any of certain Mexican plants of the genera Sebastiania and Sapium, of the spurge family: the movements of a moth larva inside the seed cause it to move about or jump.
Origin of jumping bean
An Americanism dating back to 1885–90
Also called Mexican jumping bean.
Dictionary.com Unabridged Based on the Random House Unabridged Dictionary, © Random House, Inc. 2019
a seed of any of several Mexican euphorbiaceous plants, esp species of Sebastiania, that contains a moth caterpillar whose movements cause it to jerk about
Collins English Dictionary - Complete & Unabridged 2012 Digital Edition © William Collins Sons & Co. Ltd. 1979, 1986 © HarperCollins Publishers 1998, 2000, 2003, 2005, 2006, 2007, 2009, 2012