anonymous
adj.adj. having a name that is not known or not made public. You use this when you want to keep your identity a secret.
adj. lacking a name or an acknowledged identity; of unknown authorship or origin.
The donor wants to remain anonymous.
The police received an anonymous tip that led them to the stolen car.
While the internet allows for anonymous communication, it also presents challenges for verifying the credibility of information shared by unidentified sources.
Borrowed into English around 1600 from Late Latin anonymus, from Ancient Greek ᾰ̓νώνῠμος (ănṓnŭmos, “without name”), from ᾰ̓ν- (ăn-, “un-”) with ὄνῠμᾰ (ónŭmă), Aeolic and Doric dialectal form of ὄνομᾰ (ónomă, “name”). English equivalent anonym + -ous, its full etymology being an- + -onym + -ous.
Typically used as an attributive adjective before a noun or as a predicative adjective after a linking verb.