The Collaborative International Dictionary of English v.0.48:

Pansy \Pan"sy\, n.; pl. Pansies. [F. Pens['e]e thought, pansy,
   fr. penser to think, L. pensare to weigh, ponder. See
   Pensive.] (Bot.)
   A plant of the genus Viola (Viola tricolor) and its
   blossom, originally purple and yellow. Cultivated varieties
   have very large flowers of a great diversity of colors.
   Called also heart's-ease, love-in-idleness, and many
   other quaint names.
   [1913 Webster]