Ouija board, in occultism, a device ostensibly used for obtaining messages from the spirit world, usually employed by a medium during a séance. The name derives from the French and German words for “yes” (oui and ja). The Ouija board consists of an oblong piece of wood with letters of the alphabet inscribed along its longer edge in a wide half-moon. On top of this, a much smaller heart-shaped board is placed, mounted on casters, which enable it to slide freely.
Each participant lightly places a finger on the small board, which then slides about because of the resultant pressure. The letters pointed out by the apex of the board may in some instances spell out words or even sentences. In the late 19th century, when the Ouija board was a popular pastime, it was fashionable to ascribe such happenings to discarnate spirits; more recent opinion is skeptical.