Synonyms for Occult (same or very similar meaning)
WordNet sense 1 (supernatural forces and events and beings collectively):
supernatural
WordNet sense 2 (impossible or nearly impossible to see; imperceptible by the eye):
invisible, unseeable
WordNet sense 3 (cause an eclipse of (a celestial body) by intervention):
eclipse
WordNet sense 4 (having an import not apparent to the senses nor obvious to the intelligence; beyond ordinary understanding):
mysterious, mystic, mystical, secret, orphic
WordNet sense 5 (confined to and understandable by only an enlightened inner circle):
esoteric
WordNet sense 6 (supernatural practices and techniques):
occult arts
From the ODE community, based on WordNet
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