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touch-me-not

American  
[tuhch-mee-not] / ˈtʌtʃ miˌnɒt /

noun

  1. any of several plants belonging to the genus Impatiens, of the balsam family, especially I. noli-tangere, bearing pods that, when ripe, burst on being touched, scattering the seeds.


touch-me-not British  

noun

  1. Also called: noli-me-tangere.  any of several balsaminaceous plants of the genus Impatiens, esp I. noli-me-tangere, having yellow spurred flowers and seed pods that burst open at a touch when ripe

"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

Etymology

Origin of touch-me-not

First recorded in 1590–1600