: an instrument used for measuring curved lines (as on a map) and consisting essentially of a screw with a wheel-shaped nut that is made to rotate forward along the curved lines and then backward to its original position on the screw along a straight scale

Word History


from Greek opisō backwards + English -meter; akin to Greek opisthen

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Dictionary Entries Near opisometer

Cite this Entry

“Opisometer.” Merriam-Webster.com Dictionary, Merriam-Webster, https://www.merriam-webster.com/dictionary/opisometer. Accessed 23 Jul. 2024.

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