ragweed

noun

rag·​weed ˈrag-ˌwēd 

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

Illustration of ragweed

Examples of ragweed in a Sentence

Recent Examples on the Web

The most common weed allergen is ragweed, with almost 50 million people having an allergy in the United States, according to the AAFA study. Managing your allergies To help ease your symptoms the AAFA suggests the following things: Check pollen counts and forecasts to avoid extreme pollen days. —Ashley Fredde, Idaho Statesman, 20 Apr. 2025

In rare cases, stevia may cause an allergic reaction, especially in people with a ragweed allergy. —Melissa Nieves, Verywell Health, 2 June 2025

Allergy season typically starts in early March with tree pollen and continues through the spring and summer with grass pollen, and then into the fall with ragweed pollen. —Stephen Underwood, Hartford Courant, 4 Apr. 2025

Common types include seasonal allergies (e.g., pollen, ragweed) and environmental allergies (e.g., mold, dust, pet dander). —Lindsay Curtis, Health, 25 Apr. 2025

Word History

First Known Use

1790, in the meaning defined above

Rhymes for ragweed

• accede
• agreed
• airspeed
• alkyd
• bindweed
• chickweed
• concede
• decreed
• duckweed
• exceed
• flaxseed
• impede

Kids Definition

ragweed

noun

rag·​weed ˈrag-ˌwēd 

: any of various chiefly North American weedy herbs related to the daisies and producing pollen irritating to the eyes and noses of some persons

Medical Definition

ragweed

noun

rag·​weed ˈrag-ˌwēd 

: 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