'Libel' definitions:

Definition of 'libel'

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; "The newspaper was accused of libeling him"

From: GCIDE

Libel \Li"bel\, v. t. [imp. & p. p. Libeled (-b[e^]ld) or Libelled; p. pr. & vb. n. Libeling or Libelling.]
1. To defame, or expose to public hatred, contempt, or ridicule, by a writing, picture, sign, etc.; to lampoon. [1913 Webster]
Some wicked wits have libeled all the fair. --Pope. [1913 Webster]
2. (Law) To proceed against by filing a libel, particularly against a ship or goods. [1913 Webster]

From: GCIDE

Libel \Li"bel\ (l[imac]"b[e^]l), n. [L. libellus a little book, pamphlet, libel, lampoon, dim. of liber the liber or inner bark of a tree; also (because the ancients wrote on this bark), paper, parchment, or a roll of any material used to write upon, and hence, a book or treatise: cf. F. libelle.] [1913 Webster]
1. A brief writing of any kind, esp. a declaration, bill, certificate, request, supplication, etc. [Obs.] --Chaucer. [1913 Webster]
A libel of forsaking [divorcement]. --Wyclif (Matt. v. 31). [1913 Webster]
2. Any defamatory writing; a lampoon; a satire. [1913 Webster]
3. (Law) A malicious publication expressed either in print or in writing, or by pictures, effigies, or other signs, tending to expose another to public hatred, contempt, or ridicule. Such publication is indictable at common law. [1913 Webster]
Note: The term, in a more extended sense, includes the publication of such writings, pictures, and the like, as are of a blasphemous, treasonable, seditious, or obscene character. These also are indictable at common law. [1913 Webster]
4. (Law) The crime of issuing a malicious defamatory publication. [1913 Webster]
5. (Civil Law & Courts of Admiralty) A written declaration or statement by the plaintiff of his cause of action, and of the relief he seeks. [1913 Webster]

From: GCIDE

Libel \Li"bel\ (l[imac]"b[e^]l), v. i. To spread defamation, written or printed; -- with against. [Obs.] [1913 Webster]
What's this but libeling against the senate? --Shak. [1913 Webster]
[He] libels now 'gainst each great man. --Donne. [1913 Webster]