1. noun
a) A tuft, or other excrescence or natural ornament, growing on an animals head; the comb of a cock; the swelling on the head of a serpent; the lengthened feathers of the crown or nape of bird, etc.
b) The plume of feathers, or other decoration, worn on or displayed on a helmet; the distinctive ornament of a helmet.
2. verb
Particularly with reference to waves, to reach a peak.
Wikipedia foundation.