Simple Definition of periscope

from our Learner's Dictionary

periscope

noun

ˈperəˌskoʊp

plural periscopes

: a long tube that contains lenses and mirrors and that is used to look over or around something and especially by a person in a submarine to see above the surface of the water

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“Periscope.” Merriam-Webster.com Simple Definition, Merriam-Webster, https://www.merriam-webster.com/simple/periscope. Accessed 19 Jun. 2026.

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Simple Definition of periscope

periscope

noun

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