Source : Webster's Revised Unabridged Dictionary (1913)

Slanderous \Slan"der*ous\, a.
   1. Given or disposed to slander; uttering slander.
      ``Slanderous tongue.'' --Shak.

   2. Embodying or containing slander; calumnious; as,
      slanderous words, speeches, or reports. --
      {Slan"der*ous*ly}, adv. -- {Slan"der*ous*ness}, n.

Source : WordNet®

slanderously
     adv : in a false and slanderous and defamatory manner; with
           slander or calumny [syn: {calumniously}]