Verb
The word is derived from libel
of Libel
Source: Webster's dictionarySutin 2000, pp. 363–364 Kaczynski 2010, pp. 463–465 Churton 2011, p. 357. In need of money, he launched a series of court cases against people whom he believed had libelled him, some of which proved successful. Source: Internet
He gained much publicity for his lawsuit against Constable and Co for publishing Nina Hamnett 's Laughing Torso (1932) – a book he thought libelled him – but lost the case. Source: Internet