Merriam-Webster's Collegiate® Dictionary, 11th Edition
DISGUISE
I. transitive verb (disguised; disguising)
Etymology: Middle English disgisen, from Anglo-French desguiser, deguiser, from des- dis- + guise guise
Date: 14th century
1. to change the customary dress or appearance of, to furnish with a false appearance or an assumed identity, disfigure , to obscure the existence or true state or character of ; conceal , disguisedly adverb disguisement noun disguiser noun Synonyms: see: disguise
II. noun
Date: 14th century
apparel assumed to conceal one's identity or counterfeit another's, the act of disguising,
3. form misrepresenting the true nature of something , an artificial manner ; pretense