The DICT Development Group

  Alyssum \A*lys"sum\ ([.a]*l[i^]s"s[u^]m), n. [NL., fr. Gr.
     'a`lysson, name of a plant, perh. fr. 'a priv. + ly`ssa
     raging madness.] (Bot.)
     A genus of cruciferous plants; madwort. The sweet alyssum
     ({Alyssum maritimum), cultivated for bouquets, bears small,
     white, sweet-scented flowers.
     [1913 Webster]

  alyssum
      n 1: any garden plant of the genus Alyssum having clusters of
           small yellow or white flowers [syn: alyssum, madwort]
      2: a genus of the family Cruciferae [syn: Alyssum, genus
         Alyssum]