to attack the good name or reputation of, as by uttering or publishing maliciously or falsely anything injurious; slander or libel; calumniate: The newspaper editorial defamed the politician.
2.
Archaic.to disgrace; bring dishonor upon.
3.
Archaic.to accuse.
Origin: 1275–1325;Middle Englishdefamen (< Anglo-Frenchdefamer) < Medieval Latindēfāmāre, by-form of Medieval Latin,Latindiffāmāre (dē-de- for dif-; compare Latindēfāmātus infamous) to spread the news of, slander, equivalent to dif-dif- + -fāmāre verbal derivative of fāma news, rumor, slander (see fame); replacing Middle Englishdiffamen (< Anglo-French,Old Frenchdiffamer) < Medieval Latin,Latin, as above
c.1300, from O.Fr. defamer, from M.L. defamare, from L. diffamare "to spread abroad by ill report," from dis- suggestive of ruination + fama "a report, rumor."