rag·​weed | \ ˈrag-ˌwēd How to pronounce ragweed (audio) \

Definition of ragweed

: any of various chiefly North American weedy composite herbs (genus Ambrosia) that produce highly allergenic pollen

Illustration of ragweed

Illustration of ragweed

Examples of ragweed in a Sentence

Recent Examples on the Web Longer summers could also cause some plants — including ragweed, which is common in Massachusetts — to release pollen for 19 extra days. Globe Staff, BostonGlobe.com, 22 Mar. 2022 There are other allergens that have similar seasonal effects, such as ragweed and other grasses that come in the summer and fall months every year. Timothy Fanning, San Antonio Express-News, 17 Dec. 2021 While the original book’s stories are the better of the two, Centerburg Tales has its own moments of fun, from the giant ragweed trees to the mysterious song no one can stop singing. Sarah Schutte, National Review, 25 Apr. 2021 Case’s 2018 study names upstate New York and New England as prime areas for ragweed expansion. Meryl Davids Landau, Good Housekeeping, 15 Apr. 2021 According to Rent-A-Ruminant Texas, these breeds are all effective at reducing brush overgrowth, green briars, poison ivy, ragweed and other undesirable plant species. Ryan Nickerson, Houston Chronicle, 15 Sep. 2020 Weed pollen is low/moderate, as ragweed begins to pick up. Ian Livingston, Washington Post, 18 Aug. 2020 Already, there are low amounts of ragweed in the air in Cleveland, according to the Academy of Medicine of Cleveland and Northeast Ohio. Mary Kilpatrick, cleveland, 2 Aug. 2020 Grass pollen starts to pick up in April and May, and then high ragweed counts will start to appear in September. Rebecca Hennes, Houston Chronicle, 5 Mar. 2020 See More

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

First Known Use of ragweed

1790, in the meaning defined above

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Time Traveler for ragweed

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The first known use of ragweed was in 1790

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Dictionary Entries Near ragweed



ragweed family

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Cite this Entry

“Ragweed.” Merriam-Webster.com Dictionary, Merriam-Webster, https://www.merriam-webster.com/dictionary/ragweed. Accessed 16 Aug. 2022.

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More Definitions for ragweed


rag·​weed | \ ˈrag-ˌwēd How to pronounce ragweed (audio) \

Kids Definition of ragweed

: a common weed with pollen that irritates the eyes and noses of some people


rag·​weed | \ ˈrag-ˌwēd How to pronounce ragweed (audio) \

Medical Definition of ragweed

: any of various chiefly North American weedy herbaceous plants comprising the genus Ambrosia and producing highly allergenic pollen responsible for much hay fever and asthma: as
a : an annual weed (A. artemisiifolia) with finely divided foliage that is common on open or cultivated ground in much of North America
b : a coarse annual (A. trifida) with some or all of the leaves usually deeply and palmately 3-cleft or 5-cleft

called also great ragweed

More from Merriam-Webster on ragweed

Nglish: Translation of ragweed for Spanish Speakers

Britannica.com: Encyclopedia article about ragweed


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