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

defamer \defam"er\, n.
   one who defames; a slanderer; a detractor; a calumniator.
   1913 webster

[2] : WordNet (r) 2.0

defamer
     n : one who attacks the reputation of another by slander or
         libel syn: maligner, slanderer, vilifier, libeler,
          backbiter, traducer
see also:
maligner slanderer vilifier libeler backbiter traducer 

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