recur (v.)youdaoicibaDictYouDict[recur 词源字典]
late 14c., "recover from illness or suffering;" mid-15c., "to return" (to a place), from Latin recurrere "to return, run back, hasten back," figuratively "revert, recur," from re- "back, again" (see re-) + currere "to run" (see current (adj.)). Originally of persons; application to thoughts, ideas, etc. is recorded from 1620s. Meaning "happen again" is from 1670s. Related: Recurred; recurring.[recur etymology, recur origin, 英语词源]