occult

Vague term describing a wide range of activities connected with the supernatural, from seances to black magic. The term has come to have largely sinister overtones and an association with Satanism and witchcraft.

The occult sciences include the study and practice of such paranormal phenomena as telepathy and clairvoyance. Historically, alchemy and astrology were the most important fields.

occult

In medicine, a substance that is present in small amounts but is not easily detected. Occult blood in the faeces can only be detected by a chemical test or by microscopic examination.