Incognito — Defs

01 a. [or] adv. Without being known; in disguise; in an assumed character, or under an assumed title; -- said esp. of great personages who sometimes adopt …

1.
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.” — Prior.

“The prince royal of Persia came thither incognito.” — Tatler.

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

pl. Incognitos ((#))

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.” — Sir W. Scott.