theorem (n.)youdaoicibaDictYouDict[theorem 词源字典]
1550s, from Middle French théorème (16c.) and directly from Late Latin theorema, from Greek theorema "spectacle, sight," in Euclid "proposition to be proved," literally "that which is looked at," from theorein "to look at, behold" (see theory).[theorem etymology, theorem origin, 英语词源]