able, ambiguous, amphibological, amphibolous, arcane, baffling, beguiling, bewildering, bothering, cabalistic, censored, classified, close, closed, concealed, confounding, confusing, cryptic, dark, discomposing, disconcerting, dismaying, distracting, disturbing, embarrassing, equivocal, equivocatory, esoteric, exceptional, extraordinary, fabulous, fantastic, fascinating, hermetic, hidden, hush-hush, incalculable, incognizable, incomprehensible, inconceivable, incredible, intricate, ironic, latent, marvelous, miraculous, multivocal, mysterious, mystifying, obscure, occult, outlandish, passing strange, perplexing, perturbing, phenomenal, polysemantic, polysemous, problematic, prodigious, puzzling, rare, remarkable, restricted, riddling, sealed, secret, sensational, smothered, sphinxlike, stifled, strange, striking, stupendous, suppressed, top secret, ulterior, unapparent, unapprehended, unascertained, unbeknown, unbreatheable, uncertain, uncharted, unclassified, under security, under wraps, undisclosable, undisclosed, undiscoverable, undiscovered, undivulgable, undivulged, unexplained, unexplored, unexposed, unfamiliar, unfathomed, unheard-of, unheard, unidentified, unimaginable, uninvestigated, unique, unknowable, unknown, unperceived, unplumbed, unprecedented, unrevealable, unrevealed, unspoken, unsuspected, untellable, untold, untouched, unutterable, unuttered, unwhisperable, upsetting, virgin, wonderful, wondrous