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

Example Sentences

Recent Examples on the Web 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 Antioxidant extract from Japanese knotweed, known as Nitrosigine®, works to improve blood flow and vasodilation and promote natural nitric oxide production, resulting in stronger muscle pumps and better results. Amber Smith, Discover Magazine, 17 Oct. 2022 Some set menus slyly increase awareness, like a recent series of invasive species dinners that sold out in two hours, with diners tempted by jellyfish and Japanese knotweed. Cnt Editors, Condé Nast Traveler, 5 July 2022 The now-30-year-old Nelson makes videos about magnolia blossoms, maple leaves, dandelion fritters, even invasive species like Japanese knotweed. Gabriel Popkin, Washington Post, 15 Aug. 2022 Don’t buy land invaded by Japanese knotweed, which is impossible to defeat with its spread, which can reach up to 65 feet underground. Carol Stocker,, 10 Apr. 2022 Giant hogweed and Japanese knotweed both were originally used as garden plants. Brittany Trang, Milwaukee Journal Sentinel, 10 Aug. 2021 Another problem is the Japanese knotweed that has taken over the yard. Kelly Klein, Star Tribune, 25 June 2021 See More

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 8 Jun. 2023.

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