In*cog"ni*to (?), a. or adv. [It. incognito, masc., incognita, fem., L. incognitus unknown; pref. in- not + cognitus known, p. p. of cognoscere: cf. F. incognito, fr. It. See Cognition.] Without being known; in disguise; in an assumed character, or under an assumed title; -- said esp. of great personages who sometimes adopt a disguise or an assumed character in order to avoid notice.

'T was long ago
Since gods come down incognito.

The prince royal of Persia came thither incognito.

In*cog"ni*to, n.; pl. Incognitos (#). [See Incognito, a.]

1. One unknown or in disguise, or under an assumed character or name.

2. The assumption of disguise or of a feigned character; the state of being in disguise or not recognized.

His incognito was endangered.

• Without being known; in disguise; in an assumed character, or under an assumed title
       usage note: said especially of great personages who sometimes adopt a disguise or an assumed character in order to avoid notice.
  
• One unknown or in disguise, or under an assumed character or name.
  
• The assumption of disguise or of a feigned character; the state of being in disguise or not recognized.