crest: [14] The original etymological meaning of crest appears to have been ‘tuft of hair’. It comes via Old French creste from Latin crista ‘tuft, plume’, which may be related to Latin crīnis ‘hair’ (source of the English biological term crinite ‘hairy’ [16]). If so, crest belongs to the same word family as crinoline. The notion of crest as a ‘surmounting ridge’ is a secondary semantic development, which may have given rise to the word crease. => crease
crest (n.)
early 14c., from Old French creste "tuft, comb" (Modern French crête), from Latin crista "tuft, plume," perhaps related to word for "hair" (such as crinis), but it also was used for crest of a cock or a helmet. Replaced Old English hris.
crest (v.)
late 14c., "provide with a crest," from Old French crester, from creste (see crest (n.)). Meaning "to come over the top of" is from 1832. Related: Crested; cresting.