valerian

from WordNet (r) 3.0 (2006)

valerian
    n 1: a plant of the genus Valeriana having lobed or dissected
         leaves and cymose white or pink flowers

from The Collaborative International Dictionary of English v.0.48

Valerian \Va*le"ri*an\, n. [LL. valeriana, perhaps from some
   person named Valerius, or fr. L. valere to be strong.
   powerful, on account of its medicinal virtues: cf. F.
   val['e]riane.] (Bot.)
   Any plant of the genus {Valeriana}. The root of the officinal
   valerian ({Valeriana officinalis}) has a strong smell, and is
   much used in medicine as an antispasmodic.
   [1913 Webster]

   {Greek valerian} (Bot.), a plant ({Polemonium caeruleum})
      with blue or white flowers, and leaves resembling those of
      the officinal valerian.
      [1913 Webster]