[1] : The Collaborative International Dictionary of English v.0.48

defamation \def`ama"tion\, n. oe. diffamacioun, f.
   diffamation. see defame.
   act of injuring another's reputation by any slanderous
   communication, written or oral; the wrong of maliciously
   injuring the good name of another; slander; detraction;
   calumny; aspersion.
   1913 webster

   note: in modern usage, written defamation bears the title of
         libel, and oral defamation that of slander. --burrill.
         1913 webster
see also:
defame 

[2] : WordNet (r) 2.0

defamation
     n 1: a malicious attack syn: calumny, obloquy, traducement,
           hatchet job
     2: an abusive attack on a person's character or good name syn:
         aspersion, calumny, slander, denigration
see also:
calumny obloquy traducement hatchet job aspersion slander 
denigration 

[3] : Moby Thesaurus II by Grady Ward, 1.0

24 moby thesaurus words for "defamation":
   attack, backbiting, backstabbing, belittlement, blackening,
   calumny, character assassination, defamation of character,
   defilement, denigration, depreciation, disparagement,
   malicious defamation, muckraking, mudslinging, name-calling,
   revilement, scandal, slander, smear, smear campaign, smear word,
   tale, vilification

[4] : Bouvier's Law Dictionary, Revised 6th Ed (1856)

defamation, tort. the speaking slanderous words of a person so as, de bona 
fama aliquid detrahere, to hurt his good fame. vide slander. 
     2. in the united states, the remedy for defamation is by an action on 
the case, where the words are slanderous. 
     3. in england, besides the remedy by action, proceedings may be 
instituted in the ecclesiastical court for redress of the injury. the 
punishment for defamation, in this court, is payment of costs and penance 
enjoined at the discretion of the judge. when the slander has been privately 
uttered, the penance may be ordered to be performed in a private place; when 
publicly uttered, the sentence must be public, as in the church of the 
parish of the defamed party, in time of divine service,, and the defamer may 
be required publicly to pronounce that by such words, naming them, as set 
forth in the sentence, he had defamed the plaintiff, and, therefore, that he 
begs pardon, first, of god, and then of the party defamed, for uttering such 
words. clerk's assist. 225; 3 burn's eccl. law, defamation, pl. 14; 2 chit. 
pr. 471 cooke on def. 

Defamation >> D Words
Defamation, definition of term: Defamation
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