ragwort

from WordNet (r) 3.0 (2006)

ragwort
    n 1: widespread European weed having yellow daisylike flowers;
         sometimes an obnoxious weed and toxic to cattle if consumed
         in quantity [syn: {ragwort}, {tansy ragwort}, {ragweed},
         {benweed}, {Senecio jacobaea}]
    2: American ragwort with yellow flowers [syn: {butterweed},
       {ragwort}, {Senecio glabellus}]

from The Collaborative International Dictionary of English v.0.48

Ragwort \Rag"wort`\ (r[a^]g"w[^u]rt`), n. (Bot.)
   A name given to several species of the composite genus
   {Senecio}.
   [1913 Webster]

   Note: {Senecio aureus} is the golden ragwort of the United
         States; {Senecio elegans} is the purple ragwort of
         South Africa.
         [1913 Webster]

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