unknown

Synonyms: alien anonymous concealed dark desolate distant exotic far faraway far-off foreign hidden humble incog incognito little known nameless new remote secret so-and-so strange such-and-such unapprehended unascertained uncelebrated uncharted undiscovered undistinguished unexplained unexplored unfamiliar unheard-of unidentified unnamed unnoted unperceived unrecognized unrenowned unrevealed unsung untold x

Antonyms: familiar identified known