abstruse arcane between the lines cabalistic cabbalistic censored classified close closed concealed covert dark delitescent dormant enigmatic equivocal esoteric evasive hermetic hibernating hidden hush-hush incomprehensible inexplicable inscrutable latent lurking muffled murky mysterious mystic mystical mystifying nebulous obfuscated obscure obscured occult opaque perplexing possible potential puzzling recondite restricted riddling secret secretive sleeping smothered sphinxlike stifled strange submerged suppressed tenebrous top secret ulterior unbreatheable unclear under security under the surface under wraps underlying undisclosable undisclosed undivulgable undivulged unfathomable uninformative unmanifested unrevealable unrevealed unspoken untellable untold unutterable unuttered unwhisperable vague veiled virtual