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shadow pin

American  

noun

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  1. a vertical pin set in an azimuth instrument or at the center of a compass card, indicating by the direction of its shadow the azimuth of the sun.

Etymology

Origin of shadow pin

First recorded in 1890–95

Definitions and idiom definitions from Dictionary.com Unabridged, based on the Random House Unabridged Dictionary, © Random House, Inc. 2023

Idioms from The American Heritage® Idioms Dictionary copyright © 2002, 2001, 1995 by Houghton Mifflin Harcourt Publishing Company. Published by Houghton Mifflin Harcourt Publishing Company.