Word Study
arcane
OXFORD DICTIONARY
arcane, adj. mysterious, secret; understood by few.
Derivative
arcanely adv.
Etymology
F arcane or L arcanus f. arcere shut up f. arca chest
THESAURUS
arcane
abstract, abstruse, cabalistic, censored, classified, close, closed, concealed, cryptic, dark, deep, eerie, enigmatic, esoteric, extramundane, extraterrestrial, fey, hermetic, hidden, hush-hush, hypernormal, hyperphysical, impenetrable, inscrutable, latent, mysterious, mystic, mystical, numinous, occult, otherworldly, preterhuman, preternatural, preternormal, pretersensual, profound, psychic, recondite, restricted, secret, smothered, spiritual, stifled, superhuman, supernatural, supernormal, superphysical, supersensible, supersensual, suppressed, supramundane, supranatural, top secret, transcendental, transmundane, ulterior, unaccountable, unbreatheable, uncanny, under security, under wraps, undisclosable, undisclosed, undivulgable, undivulged, unearthly, unguessed, unhuman, unknowable, unrevealable, unrevealed, unspoken, untellable, untold, unutterable, unuttered, unwhisperable, unworldly, weirdFor further exploring for "arcane" in Webster Dictionary Online