[1] : The Collaborative International Dictionary of English v.0.48

ragweed \rag"weed`\ ra^g"w=ed`, n. bot.
   a common american composite weed ambrosia artemisiaefolia
   with finely divided leaves; hogweed.
   1913 webster

   great ragweed, a coarse american herb ambrosia trifida,
      with rough three-lobed opposite leaves.
      1913 webster
see also:
ambrosia artemisiaefolia great ragweed ambrosia trifida 

[2] : The Collaborative International Dictionary of English v.0.48

wormwood \worm"wood\, n. as. werm?d, akin to ohg. wermuota,
   wormuota, g. wermuth, wermut; of uncertain origin.
   1913 webster
   1. bot. a composite plant artemisia absinthium, having
      a bitter and slightly aromatic taste, formerly used as a
      tonic and a vermifuge, and to protect woolen garments from
      moths. it gives the peculiar flavor to the cordial called
      absinthe. the volatile oil is a narcotic poison. the term
      is often extended to other species of the same genus.
      1913 webster

   2. anything very bitter or grievous; bitterness.
      1913 webster

            lest there should be among you a root that beareth
            gall and wormwood.                    --deut. xxix.
                                                  18.
      1913 webster

   roman wormwood bot., an american weed ambrosia
      artemisiaefolia; hogweed.

   tree wormwood bot., a species of artemisia probably
      artemisia variabilis with woody stems.

   wormwood hare zool., a variety of the common hare lepus
      timidus; -- so named from its color.
      1913 webster
see also:
artemisia absinthium roman wormwood ambrosia artemisiaefolia tree wormwood artemisia variabilis wormwood hare 
lepus timidus 

[3] : The Collaborative International Dictionary of English v.0.48

bitterweed \bit"terweed`\, n. bot.
   a species of ambrosia ambrosia artemisiaefolia; roman
   worm wood. --gray.
   1913 webster
see also:
ambrosia ambrosia artemisiaefolia 

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