Bible Dictionaries
Periscope

Webster's Dictionary

(1):

(n.) 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.

(2):

(n.) A general or comprehensive view.

Bibliography Information
Webster, Noah. Entry for 'Periscope'. Noah Webster's American Dictionary. https://www.studylight.org/​dictionaries/​eng/​web/​p/periscope.html. 1828.