Source : Webster's Revised Unabridged Dictionary (1913)

Masquerade \Mas`quer*ade"\, n. [F. mascarade, fr. Sp. mascarada,
   or It. mascherata. See {Mask}.]
   1. An assembly of persons wearing masks, and amusing
      themselves with dancing, conversation, or other
      diversions.

            In courtly balls and midnight masquerades. --Pope.

   2. A dramatic performance by actors in masks; a mask. See 1st
      {Mask}, 4. [Obs.]

   3. Acting or living under false pretenses; concealment of
      something by a false or unreal show; pretentious show;
      disguise.

            That masquerade of misrepresentation which
            invariably accompanied the political eloquence of
            Rome.                                 --De Quincey.

   4. A Spanish diversion on horseback.

Masquerade \Mas`quer*ade"\, v. i. [imp. & p. p. {Masqueraded};
   p. pr. & vb. n. {Masquerading}.]
   1. To assemble in masks; to take part in a masquerade.

   2. To frolic or disport in disquise; to make a pretentious
      show of being what one is not.

            A freak took an ass in the head, and he goes into
            the woods, masquerading up and down in a lion's
            skin.                                 --L'Estrange.

Masquerade \Mas`quer*ade"\, v. t.
   To conceal with masks; to disguise. ``To masquerade vice.''
   --Killingbeck.

Source : WordNet®

masquerade
     n 1: a party of guests wearing costumes and masks [syn: {masque},
           {mask}]
     2: a costume worn as a disguise at a masquerade party [syn: {fancy
        dress}, {masquerade costume}]
     3: making a false outward show; "a beggar's masquerade of
        wealth"

masquerade
     v 1: take part in a masquerade
     2: pretend to be someone or something that you are not; "he is
        masquerading as the expert on the Internet"; "This silly
        novel is masquerading as a serious historical treaty"