1 [uncountable and countable]
something that you wear to change your appearance and hide who you are, or the act of wearing this:
His disguise didn't fool anyone.
She wore dark glasses in an absurd attempt at disguise.
wearing a disguise:
The woman in the park turned out to be a police officer in disguise.
made to seem like something else that is better:
'Tax reform' is just a tax increase in disguise.