Source : Webster's Revised Unabridged Dictionary (1913)

Dissimulation \Dis*sim`u*la"tion\, n. [L. dissimulatio: cf. F.
   dissimulation.]
   The act of dissembling; a hiding under a false appearance;
   concealment by feigning; false pretension; hypocrisy.

         Let love be without dissimulation.       --Rom. xii. 9.

         Dissimulation . . . when a man lets fall signs and
         arguments that he is not that he is.     --Bacon.

         Simulation is a pretense of what is not, and
         dissimulation a concealment of what is.  --Tatler.

Source : WordNet®

dissimulation
     n : the act of deceiving [syn: {deception}, {deceit}, {dissembling}]