knotweed

noun

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
Examples are automatically compiled from online sources to show current usage. Read More Opinions expressed in the examples do not represent those of Merriam-Webster or its editors. Send us feedback.
For example, use tarps to smother a strand of Japanese knotweed. — David Beaulieu, The Spruce, 17 May 2026 Japanese knotweed’s young shoots and leaves, which appear in early spring, are edible. — Stephen Underwood, Hartford Courant, 29 Apr. 2025 Seeds of warm-season annuals like crabgrass, bindweed, knotweed and lamb’s quarters germinate in spring and plants often get a jump on growth before heat-loving grasses like bermudagrass get started. — Kim Toscano, Southern Living, 8 Mar. 2026 Complexity smothers everything, like Japanese knotweed. — Adrian Wooldridge, Twin Cities, 6 Dec. 2025 See All Example Sentences for knotweed

Word History

First Known Use

1884, in the meaning defined above

Time Traveler
The first known use of knotweed was in 1884

Rhymes for knotweed

See All Rhymes for knotweed

Browse Nearby Words

knotty rhatany
knotweed
knotweed spurge
See all Nearby Words

Cite this Entry

“Knotweed.” Merriam-Webster.com Dictionary, Merriam-Webster, https://www.merriam-webster.com/dictionary/knotweed. Accessed 7 Jul. 2026.

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