The Collaborative International Dictionary of English v.0.48:

Cicuta \Ci*cu"ta\, n. [L., the poison hemlock.] (Bot.)
   a genus of poisonous umbelliferous plants, of which the water
   hemlock or cowbane is best known.
   [1913 Webster]

   Note: The name cicuta is sometimes erroneously applied to
         Conium maculatum, or officinal hemlock.
         [1913 Webster]

WordNet (r) 3.0 (2006):

Cicuta
    n 1: small genus of perennial herbs having deadly poisonous
         tuberous roots: water hemlock [syn: Cicuta, genus
         Cicuta]