Masquerader (noun)

1. A person who takes part in a masquerade, wearing a mask or costume to conceal their identity.
2. A person who disguises themselves or acts as someone else, especially for purposes of deception or disguise.

Origin:

The word masquerader comes from the middle english word "masquere," meaning to wear a mask or disguise, and the suffix -er, indicating a person who performs an action.

Examples:

1. The masqueraders at the carnival danced in the streets, their masks hiding their faces.
2. The masquerader was a skilled actor, who could impersonate anyone with ease.
3. The masquerade ball was a festive event, with guests dressed in elaborate costumes and masks.
4. The masquerader was a thief, who had successfully disguised himself as a wealthy businessman.
5. The masquerader was an undercover detective, who had infiltrated the criminal organization to gather evidence.