Oc-cŭlt’, a.

a. [Lat. occultus, p. p. of occulere, to cover up, hide, from prefix ob and colere, to cultivate, till, tend; Fr. occulte, Sp. oculto, It. occulto.] Hidden from the eye or understanding; invisible; secret; unknown; undiscovered; undetected. “Occult guilt.” Shak.

It is of an occult kind, and is so insensible in its advances as to escape observation. I. Taylor.

Occult line (Geom.), a dry or obscure line, which is drawn as a necessary part of the construction of a figure or problem, but which is not intended to appear after the plan is finished. Barlow.—Occult qualities, in the schools, those qualities whose effects only were observed, but the nature and relations of whose productive agencies were undetermined.—Occult sciences, those imaginary 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.