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

This North American native beauty is too often mistaken for ragweed and incorrectly deemed a nuisance. —Carl R. Gold, Baltimore Sun, 7 Mar. 2026

Weed pollen from ragweed, thistle, sagebrush, and mugwort typically peaks later in summer and early fall, with the highest weed pollen levels expected across the Rockies this year. —Michele Laufik, Martha Stewart, 4 Mar. 2026

Later in summer and into early fall, weed pollen from ragweed, sagebrush, and thistle will take over. —Jessica Safavimehr, Southern Living, 4 Mar. 2026

For many people, ragweed is worse than cedar fever or oak. —Nicole Villalpando, Austin American Statesman, 11 Feb. 2026

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