Pertaining to any of the ancient mysteries.Hidden from or obscure to human knowledge or comprehension: pertaining to what is obscure or incomprehensible; mysterious; dark; obscure; specifically, expressing a sense comprehensible only to a higher grade of intelligence or to those especially initiated.Of or pertaining to mystics or mysticism.In the civil law of Louisiana, sealed or closed: as, a Mystic testamentSynonyms and Cabalistic, etc. See mysterious.n. One who accepts or preaches some form of mysticism; specifically [capitalized], one who holds to the possibility of direct conscious and unmistakable intercourse with God by a species of ecstasy. See Quietist, Pietist, Gichtelian.