Periscopic \Per`i*scop"ic\, a. [Cf. F. p['e]riscopique.]
Viewing all around, or on all sides.
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2. of or relating to a periscope[2].
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{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.
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