Etymology

Noun

1. A party or assembly of people wearing masks, and amusing themselves with dancing, conversation, or other diversions.

   In courtly balls and midnight masquerades - Alexander Pope

2. A dramatic performance by actors in masks; a mask. See “mask”
3. Acting or living under false pretenses; concealment of something by a false or unreal show; pretentious show; disguise.

   I was invited to the masquerade at their home.

   That masquerade of misrepresentation which invariably accompanied the political eloquence of Rome - Thomas de Quincey

4. A Spanish diversion on horseback.

Verb

1. To assemble in masks; to take part in a masquerade.

   I'm going to masquerade as the wikipede. What are you going to dress up as?

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

   He masqueraded as my friend until the truth finally came out.

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

3. To conceal with masks; to disguise.

   To masquerade vice - Killingbeck