Definition of periscope
: a tubular optical instrument containing lenses and mirrors by which an observer obtains an otherwise obstructed field of view
Recent Examples of periscope from the Web
There’s also an electro-optical periscope and an infrared camera mounted on the conning tower—
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Origin and Etymology of periscope
International Scientific Vocabulary
First Known Use: 1879
PERISCOPE Defined for English Language Learners
Definition of periscope for English Language Learners
: 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
PERISCOPE Defined for Kids
Definition of periscope for Students
: an instrument containing lenses and mirrors by which a person (as on a submarine) can get a view that would otherwise be blocked
Seen and Heard
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