(1):
(a.) Designed for, and understood by, the specially initiated alone; not communicated, or not intelligible, to the general body of followers; private; interior; acroamatic; - said of the private and more recondite instructions and doctrines of philosophers. Opposed to exoteric.
(2):
(a.) Marked by secrecy or privacy; private; select; confidential; as, an esoteric purpose; an esoteric meeting.
(3):
(n.) One who believes, or is an initiate, in esoteric doctrines or rites.
(4):
(n.) An esoteric doctrine or treatise; esoteric philosophy; esoterics.