Nouns

(n)masquerade, masquerade party, masque, maska party of guests wearing costumes and masks
(n)fancy dress, masquerade, masquerade costumea costume worn as a disguise at a masquerade party
(n)masquerade, charademaking a false outward show“a beggar's masquerade of wealth”

Verbs

(v)masqueradetake part in a masquerade
(v)masqueradepretend to be someone or something that you are not“he is masquerading as an expert on the internet”, “This silly novel is masquerading as a serious historical treaty”