1. To assume a false identity: Athena went to the party disguised as Marie Antoinette.
2. To change the usual appearance, sound, etc. of a person or or something: Glenda disguised herself as a musician so she could get into the concert hall early.
3. To hide something so it will not be noticed nor recognized: The workers disguised their happiness when the rain kept them from working on the building for over an hour as they played cards in a shelter.