Related Clues:
- Not widely known
- Enigmatic
- Just for a few
- Understood by very few
- For initiates only
- Understood by a select few
- Understood by only a few
- Difficult to understand
- Secret, mysterious
- I set core up to be mysterious
- Privileged or confidential among coteries
- Secret kind of coteries
- Mysterious to all but a chosen few
- Intelligible only to informed people in coteries
- Abstruse, arcane