smartweed

[ smahrt-weed ]
/ ˈsmɑrtˌwid /

noun

any of several weeds of the genus Polygonum, having a smarting, acrid juice.

Origin of smartweed

First recorded in 1780–90; smart + weed1
Dictionary.com Unabridged Based on the Random House Unabridged Dictionary, © Random House, Inc. 2019

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