arcane

/ɑɹˈkeɪn/
/ɑɹˈkeɪn/

adjective

  1. Understood by only a few.

    "arcane rituals"

  2. (by extension) Obscure, mysterious.

    "arcane details"

  3. Requiring secret or mysterious knowledge to understand.

  4. Extremely old (e.g. interpretation or knowledge), and possibly irrelevant.

    "An arcane law"

Synonyms: clandestine, enigmatic, esoteric, recondite, esoteric
Antonyms: mundane