libellous

from WordNet (r) 3.0 (2006)

libellous
    adj 1: (used of statements) harmful and often untrue; tending to
           discredit or malign [syn: {calumniatory}, {calumnious},
           {defamatory}, {denigrative}, {denigrating},
           {denigratory}, {libellous}, {libelous}, {slanderous}]

from The Collaborative International Dictionary of English v.0.48

Libelous \Li"bel*ous\ (l[imac]"b[e^]l*[u^]s), a.
   Containing or involving a libel; defamatory; containing that
   which exposes some person to public hatred, contempt, or
   ridicule; as, a libelous pamphlet. [Written also
   {libellous}.] -- {Li"bel*ous*ly}, adv.
   [1913 Webster]