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