Webster’s Revised Unabridged Dictionary · 1913
Skiascope
Ski′a·scope, Sci′a·scope, n. [Gr. σκιά a shadow + -scope.] (Med.) A device for determining the refractive state of the eye by observing the movements of the retinal lights and shadows. — Ski·as′co·py (#), Ski·as′co·py (#), n.