The Collaborative International Dictionary of English v.0.48:

Coleus \Co"le*us\, n. [NL., fr. Gr. ? a sheath; -- referring to
   the manner in which the stamens are united.] (Bot.)
   A plant of several species of the Mint family, cultivated for
   its bright-colored or variegated leaves.
   [1913 Webster]

WordNet (r) 3.0 (2006):

coleus
    n 1: any of various Old World tropical plants of the genus
         Coleus having multicolored decorative leaves and spikes of
         blue flowers [syn: coleus, flame nettle]