diffamer betyder på engelska

defame [defamed, defaming, defames]▼◼◼◼(to harm, to diminish the reputation of)
verb
[UK: dɪ.ˈfeɪm] [US: də.ˈfeɪm]

vilify [vilified, vilified]▼◼◼◻(say defamatory things about; to speak ill of)
verb
[UK: ˈvɪ.lɪ.faɪ] [US: ˈvɪ.lə.ˌfaɪ]

smear [smeared, smearing, smears]▼◼◼◻(to damage someone's reputation by slandering, making false accusations)
verb
[UK: smɪə(r)] [US: ˈsmɪr]

traduce [traduced, traducing, traduces]▼(to malign by making malicious and false or defamatory statements)
verb
[UK: trə.ˈdjuːs] [US: trə.ˈdjuːs]

backbite [backbit, backbitten, backbiting, backbites]▼(to make defamatory statements about another)
verb
[UK: ˈbæk.baɪt] [US: ˈbæk.ˌbaɪt]

diss▼(to put someone down or show verbal disrespect)
verb
[UK: ˈdɪs] [US: ˈdɪs]