• WordNet 3.6
    • n butterweed any of several yellow-flowered plants of the genus Packera; often placed in genus Senecio
    • n butterweed American ragwort with yellow flowers
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Webster's Revised Unabridged Dictionary
    • n Butterweed (Bot) An annual composite plant of the Mississippi valley (Senecio lobatus).
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Century Dictionary and Cyclopedia
    • n butterweed A common name of the horseweed, Erigeron Canadense, and of the Senecio lobatus.
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