Esoteric, abstruse; (in particular) taught orally to select students and not disseminated.
Based on lectures or exposition by monologue.
Esoteric.
Related to the occult; pertaining to mysticism, magic, or astrology.
Secret; hidden from general knowledge; undetected.
Supernatural affairs.
To dissimulate, conceal, or obfuscate.
To cover or hide from view.