horse·​weed | \ ˈhȯrs-ˌwēd How to pronounce horseweed (audio) \

Definition of horseweed

1 : a common annual American composite herb (Conyza canadensis synonym Erigeron canadensis) with an erect usually hairy stem and small discoid heads of yellow disk flowers
2 : a coarse annual North American ragweed (Ambrosia trifida)

Examples of horseweed in a Sentence

Recent Examples on the Web Some examples are sharp point fluvellin, velvetleaf, puncturevine, horseweed, western bittercress and oxalis., "How to defend lawns, gardens against invasive weeds," 27 Feb. 2018 Yet tolerance to 2,4-D has already been documented in several weed species that have elsewhere become glyphosate-resistant superweeds, including waterhemp and horseweed. Brandon Keim, WIRED, "The Next Generation of GM Crops Has Arrived—And So Has the Controversy," 24 June 2014

These example sentences are selected automatically from various online news sources to reflect current usage of the word 'horseweed.' Views expressed in the examples do not represent the opinion of Merriam-Webster or its editors. Send us feedback.

First Known Use of horseweed

1790, in the meaning defined at sense 1

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The first known use of horseweed was in 1790

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Cite this Entry

“Horseweed.” The Dictionary, Merriam-Webster Inc., Accessed 28 January 2020.

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Comments on horseweed

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showing steady, earnest care and effort

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