incognito (adj) – under a name or title meant to escape public notice; with a concealed identity
BREAKDOWN: IN- (not) + COGN- (know)
— terra incognita is a term used to describe lands or regions that have not been mapped or documented, now used metaphorically to describe any unexplored subject or field of research
This word is built on the root COGN-, which means to learn or know.
Common COGN- words include recognize.
More esoteric COGN- words include cognizable and cognoscente.