a tuft, or other excrescence or natural ornament, growing on an animal's 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.-the plume of feathers, or other decoration, worn on a helmet; the distinctive ornament of a helmet, indicating the rank of the wearer; hence, also, the helmet.-a bearing worn, not upon the shield, but usually above it, or separately as an ornament for plate, liveries, and the like. it is a relic of the ancient cognizance. see cognizance, 4.-the upper curve of a horse's neck.-the ridge or top of a wave.-the summit of a hill or mountain ridge.-the helm or head, as typical of a high spirit; pride; courage.-the ornamental finishing which surmounts the ridge of a roof, canopy, etc.-the top line of a slope or embankment.-to furnish with, or surmount as, a crest; to serve as a crest for.-to mark with lines or streaks, like, or regarded as like, waving plumes.-to form a crest.