A disguise was the deliberate concealment of an individual's identity. Elements of a disguise could include a costume, make-up, wig, and an alias.
Broik met with a Bajoran, who came in on a a transport at an airlock in 2372. Jake Sisko, who watched the arrival, supposed that the latter was "a thief [who] disguises himself as a monk so he can swindle a Ferengi." (DS9: "The Muse")