activity (n.)youdaoicibaDictYouDict[activity 词源字典]
c. 1400, "active or secular life," from Old French activité, from Medieval Latin activitatem (nominative activitas), a word in Scholastic philosophy, from Latin activus (see active). Meaning "state of being active, briskness, liveliness" recorded from 1520s; that of "capacity for acting on matter" is from 1540s.[activity etymology, activity origin, 英语词源]