periscope

Definitions

General Science

  • noun a long tubular optical instrument through which someone can see objects that are out of the direct line of sight

Cricket

  • noun a bat held above the batsman’s head when he ducks under a bouncer

Military

  • noun an optical instrument, which enables an observer on a lower level (e.g. in a submerged submarine or at the bottom of a trench) to see things on a higher level (such as on the surface of the sea or ground)
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