The Collaborative International Dictionary of English v.0.48:

Cymose \Cy"mose\ (s?"m?s; 277), Cymous \Cy"mous\ (s?"m?s), a.
   [L. cymosus full of shoots: cf. FF. cymeux. See Cyme.] (Bot.)
   Having the nature of a cyme, or derived from a cyme; bearing,
   or pertaining to, a cyme or cymes.
   [1913 Webster]

WordNet (r) 3.0 (2006):

cymose
    adj 1: having a usually flat-topped flower cluster in which the
           main and branch stems each end in a flower that opens
           before those below it or to its side