Meaning

noun a false and malicious publication printed for the purpose of defaming a living person

noun the written statement of a plaintiff explaining the cause of action (the defamation) and any relief he seeks

verb print slanderous statements against

originFrom Middle English libel, from Old French libelle, from Latin libellus (“petition”, literally “booklet”). Doublet of libelle.

Etymology from Wiktionary, CC BY-SA 3.0