sapphire (n.)

"precious stone next in hardness to a diamond," mid-13c., from Old French saphir (12c.) and directly from Latin sapphirus (source also of Spanish zafir, Italian zaffiro), from Greek sappheiros "blue stone" (the gem meant apparently was not the one that now has the name, but perhaps rather "lapis lazuli," the modern sapphire being perhaps signified by Greek hyakinthos), from a Semitic source (compare Hebrew sappir "sapphire"), but probably not ultimately from Semitic. Some linguists propose an origin in Sanskrit sanipriya, a dark precious stone (perhaps sapphire or emerald), literally "sacred to Saturn," from Sani "Saturn" + priyah "precious." In Renaissance lapidaries, it was said to cure anger and stupidity. As an adjective from early 15c. Related: Sapphiric; sapphirine.