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green bean

noun
  1. the immature green pod of the kidney bean, eaten as a vegetable.

Origin of green bean

An Americanism dating back to 1940–45
Also called string bean, stringless bean.
Dictionary.com Unabridged Based on the Random House Unabridged Dictionary, © Random House, Inc. 2018
British Dictionary definitions for green bean

green bean

noun
  1. any bean plant, such as the French bean, having narrow green edible pods when unripe
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