Exclusive; restricted; erudite The term implies being limited to specialists or an exclusive inner circle by a quality of being too complex, scholarly or profound for popular dissemination or understanding
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
If you describe something as esoteric, you mean it is known, understood, or appreciated by only a small number of people. esoteric knowledge. a spoiled aristocrat with pretentious airs and esoteric tastes. known and understood by only a few people who have special knowledge about something (esoterikos, from esotero , from eiso )
(Greek, those within) Exoteric, those without The term originated with Pythagoras, who stood behind a curtain when he gave his lectures Those who were allowed to attend the lectures, but not to see his face, he called his exoteric disciples; but those who were allowed to enter the veil, his esoteric Aristotle adopted the same terms, though he did not lecture behind a curtain He called those who attended his evening lectures, which were of a popular character, his exoterics: and those who attended his more abstruse morning lectures, his esoterics