incognito
adj., adv.
1640s, from Italian incognito "unknown," especially in connection with traveling, from Latin incognitus "unknown," from in- "not, opposite of, without" (see in-(1)) + cognitus, past participle of cognoscere "to get to know" (see cognizance). Fem. form incognita was maintained through 19c. by those scrupulous about Latin. Incog was a common 18c. colloquial abbreviation.
〔李〕[in-=not不;co-=completely完全;gnit=to know知;-o a.=-ing ……的→“not being known 不为人知的”→] Ⅰ a. with one's name hidden隐姓埋名的