mobility (n.)youdaoicibaDictYouDict[mobility 词源字典]
early 15c., "capacity for motion," from Old French mobilité "changeableness, inconsistency, fickleness," from Latin mobilitatem (nominative mobilitas) "activity, speed," figuratively "changeableness, fickleness, inconstancy," from mobilis (see mobile (adj.)). Socio-economics sense is from 1900 and writers in sociology.[mobility etymology, mobility origin, 英语词源]