ragweed

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rag·weed

 (răg′wēd′)
n.
1. Any of various weeds of the genus Ambrosia of the composite family, having small, greenish, unisexual flower heads and producing abundant pollen that is one of the chief causes of hay fever.
2. Chiefly British Ragwort.

[From the ragged shape of its leaves.]

ragweed

(ˈræɡˌwiːd)
n
(Plants) any plant of the chiefly North American genus Ambrosia, such as A. artemisiifolia (common ragweed): family Asteraceae (composites). Their green tassel-like flowers produce large amounts of pollen, which causes hay fever. Also called: ambrosia

rag•weed

(ˈrægˌwid)

n.
any of the composite plants of the genus Ambrosia, the airborne pollen of which is the most prevalent cause of autumnal hay fever.
[1650–60; so called from its ragged appearance]
ThesaurusAntonymsRelated WordsSynonymsLegend:
Noun1.ragweed - widespread European weed having yellow daisylike flowersragweed - widespread European weed having yellow daisylike flowers; sometimes an obnoxious weed and toxic to cattle if consumed in quantity
genus Senecio, Senecio - enormous and diverse cosmopolitan genus of trees and shrubs and vines and herbs including many weeds
weed - any plant that crowds out cultivated plants
2.ragweed - any of numerous chiefly North American weedy plants constituting the genus Ambrosia that produce highly allergenic pollen responsible for much hay fever and asthmaragweed - any of numerous chiefly North American weedy plants constituting the genus Ambrosia that produce highly allergenic pollen responsible for much hay fever and asthma
genus Ambrosia - comprising the ragweeds; in some classification considered the type genus of a separate family Ambrosiaceae
Ambrosia artemisiifolia, common ragweed - annual weed with finely divided foliage and spikes of green flowers; common in North America; introduced elsewhere accidentally
Ambrosia trifida, great ragweed - a coarse annual with some leaves deeply and palmately three-cleft or five-cleft
Ambrosia psilostachya, perennial ragweed, western ragweed - coarse perennial ragweed with creeping roots of dry barren lands of southwestern United States and Mexico
weed - any plant that crowds out cultivated plants
Translations

ragweed

[ˈrægwiːd] Nambrosía f

ragweed

n (bot) ambrosía