incog
adjective
[ ɪnˈkɒɡ ]
• (of a person) having one's true identity concealed.
• "the incog spectators retreated from there as quickly as possible"
incog
adverb
• in a way that conceals one's true identity.
• "it was difficult to travel incog"
Origin:
early 18th century: abbreviation of incognito.