- Abstruse
- Arcane
- Coteries in other places are difficult to understand
- Coteries strange and hard to understand
- Obscure: likely to be understood by a few only
- Secret, mysterious
- 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.