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

valerian \vale"rian\, 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'eriane. 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
see also:
valeriana valeriana officinalis greek valerian polemonium caeruleum 

[2] : WordNet (r) 2.0

valerian
     n : a plant of the genus valeriana having lobed or dissected
         leaves and cymose white or ink flowers

Valerian >> V Words
Valerian, definition of term: Valerian
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