The Collaborative International Dictionary of English v.0.48:

Cockscomb \Cocks"comb`\ (k[o^]ks"k[=o]m`), n. [1st cock, n. +
   comb crest.]
   1. See Coxcomb.
      [1913 Webster]

   2. (Bot.) A plant (Celosia cristata), of many varieties,
      cultivated for its broad, fantastic spikes of brilliant
      flowers; -- sometimes called garden cockscomb. Also the
      Pedicularis, or lousewort, the Rhinanthus
      Crista-galli, and the Onobrychis Crista-galli.
      [1913 Webster]

WordNet (r) 3.0 (2006):

cockscomb
    n 1: garden annual with featherlike spikes of red or yellow
         flowers [syn: cockscomb, common cockscomb, Celosia
         cristata, Celosia argentea cristata]
    2: a conceited dandy who is overly impressed by his own
       accomplishments [syn: coxcomb, cockscomb]
    3: a cap worn by court jesters; adorned with a strip of red
       [syn: cockscomb, coxcomb]
    4: the fleshy red crest on the head of the domestic fowl and
       other gallinaceous birds [syn: comb, cockscomb,
       coxcomb]