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knapweed

[nap-weed]
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noun

any composite plant of the genus Centaurea, especially the weedy C. nigra, having rose-purple flowers set on a dark-colored, knoblike bract.

Origin of knapweed

First recorded in 1400–50, knapweed is from the late Middle English word knopwed. See knop, weed1
Also called hardheads, Spanish button.
Dictionary.com Unabridged Based on the Random House Unabridged Dictionary, © Random House, Inc. 2019

Examples from the Web for knapweed

Historical Examples of knapweed

  • The seeds of brook-lime, flax, and knapweed the twite seems partial to, and this wild-weed field is to them a very paradise.

  • The moth is out in July and in August, and may often be seen resting on the flowers of knapweed (Centaurea) in the daytime.

  • The knapweed was stunted and the scabious blooms drooped towards the dusty pasture.

    Sinister Street, vol. 1

    Compton Mackenzie

British Dictionary definitions for knapweed

knapweed

noun

any of several plants of the genus Centaurea, having purplish thistle-like flowers: family Asteraceae (composites)See also centaury (def. 2), hardheads

Word Origin for knapweed

C15 knopwed; see knop, weed 1
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