intrusion (n.)youdaoicibaDictYouDict[intrusion 词源字典]
late 14c., from Old French intrusion (14c.), from Medieval Latin intrusionem (nominative intrusio) "a thrusting in," noun of action from past participle stem of Latin intrudere, from in- "in" (see in- (2)) + trudere "to thrust, push" (see extrusion).[intrusion etymology, intrusion origin, 英语词源]