oppugn (v.)youdaoicibaDictYouDict[oppugn 词源字典]
mid-15c., from Latin oppugnare "to fight against, attack, assail," from ob- "toward, against" (see ob-) + pugnare "to fight" (see pugnacious). Related: Oppugned; oppugning.[oppugn etymology, oppugn origin, 英语词源]