Occult /(?)/

Oc·cult

Occult

Hidden from the eye or the understanding; invisible; secret; concealed; unknown.
It is of an occult kind, and is so insensible in its advances as to escape observation.
— I. Taylor.

Occult line: a line drawn as a part of the construction of a figure or problem, but not to appear in the finished plan.
Occult qualities: those qualities whose effects only were observed, but the nature and relations of whose productive agencies were undetermined; -- so called by the schoolmen.
Occult sciences: those sciences of the Middle Ages which related to the supposed action or influence of occult qualities, or supernatural powers, as alchemy, magic, necromancy, and astrology.

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