Source : Webster's Revised Unabridged Dictionary (1913)

Litigation \Lit`i*ga"tion\, n. [L. litigatio, fr. litigare to
   dispute, litigate; lis, litis, dispute, lawsuit (OL. stlis) +
   agere to carry on. See {Agent}.]
   The act or process of litigating; a suit at law; a judicial
   contest.

Source : WordNet®

litigation
     n : a legal proceeding in a court; a judicial contest to
         determine and enforce legal rights [syn: {judicial
         proceeding}]