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early 15c. "above nature, transcending nature, belonging to a higher realm," from Medieval Latin supernaturalis "above or beyond nature," from Latin super "above" (see super-) + natura "nature" (see nature). Originally with more of a religious sense, "of or given by God, divine; heavenly;" association with ghosts, etc., has predominated since c.1799.
1580s, from supernatural (adj.).