n. [ Pref. peri- + -scope. ] A general or comprehensive view. [ archaic ] [ 1913 Webster ]
2. An optical instrument of tubular shape containing an arrangement of lenses and mirrors (or prisms), allowing a person to observe a field of view otherwise obstructed, as beyond an obstructing object or (as in submarines) above the surface of the water. [ PJC ]
a. [ Cf. F. périscopique. ] Viewing all around, or on all sides. [ 1913 Webster ]
2. of or relating to a periscope{ 2 }. [ 1913 Webster ]
Periscopic spectacles (Opt.), spectacles having concavo-convex or convexo-concave lenses with a considerable curvature corresponding to that of the eye, to increase the distinctness of objects viewed obliquely. [ 1913 Webster ]