unity (n.)youdaoicibaDictYouDict[unity 词源字典]
c. 1300, "state or property of being one," from Anglo-French unite, Old French unite "uniqueness, oneness" (c. 1200), from Latin unitatem (nominative unitas) "oneness, sameness, agreement," from unus "one" (see one).[unity etymology, unity origin, 英语词源]