The TARDIS was disguised as a police box. (TV: An Unearthly Child)
The chameleon circuit provided TARDISes with a disguise which allowed them to blend into their surroundings. The Doctor's TARDIS was disguised as a police box in 1963, and was left stuck in this form as the chameleon circuit broke down. (TV: An Unearthly Child) Bill Potts questioned the practicality of a disguise that had "pull to open" on it. (TV: The Pilot)
Skin suits were disguises which were used most notably by the Slitheen family. (TV: Aliens of London/World War Three)
Historians who had been allowed access to the "Monster Vaults" of the databanks in the Doctor's TARDIS observed that an Abzorbaloff could disguise their form with a morphic illusion and their voice by putting on an accent, but could never disguise their villainous intent. (PROSE: The Monster Vault, TV: Love & Monsters)
The Saxon Master disguised himself as "Razor" when stranded on Floor 1056. When he met Missy, he noted that he "loved" disguises, asking if his successor continued to. (TV: World Enough and Time)
Supergirl was a "huge fan of disguises". (WC: Supergirl Meets E.T.)