defamatory (adj.)

"containing defamation, caluminous, injurious to reputation," 1590s, from Middle French diffamatoire, Medieval Latin diffamatorius "tending to defame," from diffamat-, past-participle stem of diffamare"to spread abroad by ill report, make a scandal of," from dis-, here probably suggestive of ruination, + fama "a report, rumor" (from PIE root *bha- (2) "to speak, tell, say"). Earlier in the same sense was defamative (c. 1500).