volubility (n.)youdaoicibaDictYouDict[volubility 词源字典]
1570s, from Middle French volubilité (16c.) or directly from Latin volubilitatem (nominative volubilitas) "a rapid turning," figuratively "fluency (of speech)," from volubilis (see voluble).[volubility etymology, volubility origin, 英语词源]