roof prism

noun

: a glass prism used in an optical range finder and other instruments that performs the double function of changing the direction of the light rays by 90 degrees and reversing the image right to left compare porro prism

Word History

First Known Use

1904, in the meaning defined above

Time Traveler
The first known use of roof prism was in 1904

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Dictionary Entries Near roof prism

roof plate

roof prism

roof rack

See More Nearby Entries 

Cite this Entry

“Roof prism.” Merriam-Webster.com Dictionary, Merriam-Webster, https://www.merriam-webster.com/dictionary/roof%20prism. Accessed 23 Nov. 2024.

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