knot·​weed ˈnät-ˌwēd How to pronounce knotweed (audio)
: any of several herbs (genus Polygonum) of the buckwheat family with leaves and bracts jointed and having a very short petiole
broadly : polygonum

Examples of knotweed in a Sentence

Recent Examples on the Web No offense to your prize camellia, but the garden is the least of your worries with Japanese knotweed. Melissa Locker, Southern Living, 7 Sep. 2023 Weed killers can also help in the process of removing Japanese knotweed. Melissa Locker, Southern Living, 7 Sep. 2023 The erosion caused by knotweed also drives off fish and wildlife. Claire Reid, Journal Sentinel, 8 Aug. 2023 From Japanese knotweed to kudzu vines, these invasive species cause problems throughout the world. Ed Yong, Discover Magazine, 5 Mar. 2012 For more information about knotweed, identifying the plant and strategies for removing and controlling it, check out this factsheet by the DNR. Claire Reid, Journal Sentinel, 8 Aug. 2023 Alpine Fleece Flower: Known as alpine knotweed or Jimson knotweed, this perennial boasts several stems and grows well in areas impacted by landslides and avalanche shoots. Jace Bauserman, Field & Stream, 2 Aug. 2023 Japanese knotweed's antioxidant component, Nitrosigine®, promotes natural nitric oxide production and stronger muscle pumps by increasing blood flow and vasodilation. Amber Smith, Discover Magazine, 17 Oct. 2022 In coming months, the goats will also serve as Arboretum landscapers, munching through stands of poison ivy and Japanese knotweed. Joel Millman, WSJ, 17 Jan. 2023

These examples are programmatically compiled from various online sources to illustrate current usage of the word 'knotweed.' Any opinions expressed in the examples do not represent those of Merriam-Webster or its editors. Send us feedback about these examples.

Word History

First Known Use

1884, in the meaning defined above

Time Traveler
The first known use of knotweed was in 1884

Dictionary Entries Near knotweed

Cite this Entry

“Knotweed.” Dictionary, Merriam-Webster, Accessed 18 Jun. 2024.

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