ragweed

noun
rag·​weed | \ˈrag-ˌwēd \

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

Frumkin said ragweed and poison ivy trigger more powerful allergic reactions with higher carbon dioxide levels. Kelsey Ryan, kansascity, "Are your allergies getting worse? Climate change may be to blame," 19 June 2018 Frumkin said ragweed and poison ivy trigger more powerful allergic reactions with higher carbon dioxide levels. Washington Post, "Looking for signs of global warming? It’s all around you," 19 June 2018 Frumkin said ragweed and poison ivy trigger more powerful allergic reactions with higher carbon dioxide levels. Seth Borenstein, BostonGlobe.com, "Looking for signs of global warming? They’re all around you," 19 June 2018 High ragweed pollen days have increased by between 15 and 29 days since 1990 in a swath of the country from Oklahoma City north to Winnipeg, Canada, according to a U.S. Department of Agriculture study. Seth Borenstein, Fox News, "Not just heat: Climate change signs can be seen all around," 19 June 2018 High ragweed days across America swelled from 1990 to 2016, according to a study by the U.S. Department of Agriculture’s Lewis Ziska. Washington Post, "Looking for signs of global warming? It’s all around you," 19 June 2018 High ragweed days across America swelled from 1990 to 2016, according to a study by the U.S. Department of Agriculture’s Lewis Ziska. Kelsey Ryan, kansascity, "Are your allergies getting worse? Climate change may be to blame," 19 June 2018 In general, pollen is emerging earlier in the year and the season is stretching out longer and longer, especially pollen from ragweed. Umair Irfan, Vox, "It’s not your imagination. Allergy season gets worse every year.," 28 Apr. 2018 Tree pollen and ragweed pollen is not expected to make an impact. William Axford, Houston Chronicle, "Rain expected to hit Houston Friday and Saturday, followed by sunshine on Sunday," 4 May 2018

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.

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First Known Use of ragweed

1790, in the meaning defined above

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Dictionary Entries near ragweed

ragù

raguly

Ragusa

ragweed

ragweed family

rag wheel

ragwork

Statistics for ragweed

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Time Traveler for ragweed

The first known use of ragweed was in 1790

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More Definitions for ragweed

ragweed

noun

English Language Learners Definition of ragweed

: any one of a group of North American plants that release a lot of pollen into the air and that can cause allergic reactions in some people

ragweed

noun
rag·​weed | \ˈrag-ˌwēd \

Kids Definition of ragweed

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

ragweed

noun
rag·​weed | \ˈrag-ˌwēd \

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

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More from Merriam-Webster on ragweed

Rhyming Dictionary: Words that rhyme with ragweed

Spanish Central: Translation of ragweed

Nglish: Translation of ragweed for Spanish Speakers

Britannica.com: Encyclopedia article about ragweed

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