"highly chromatic deep red color," early 15c., cremesin, "cloth dyed deep purplish-red," also as an adjective, "of a crimson color," from Old Italian carmesi, cremesi (c. 1300), later carmisino, cremesinus, "crimson color; cochineal dye," from Arabic qirmizī (see kermes). For similar transfer of the dye word to generic use for "red," compare Old Church Slavonic čruminu, Russian čermnyj "red," from the same source. The French form in 15c.-16c. when the word entered English was cramoisin. "The word in Italian came from Arabic, and the word in all other European languages came from Italian via exports of silk cloths from Italy." ["English Words of Arabic Ancestry"]
c. 1600, "to make crimson" (transitive), from crimson (n.). From 1805 as "to become crimson" (intransitive). Related: Crimsoned; crimsoning.