shadow pin

noun

, Navigation.

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.

Word History and Origins

Origin of shadow pin¹

First recorded in 1890–95

Example Sentences

It is also provided with an azimuth circle or mirror and a shadow pin or style placed in the centre of the glass cover, by either of which the variable angle between the compass north and true north, called the “total error,” or variation and deviation combined, can be observed.

From Project Gutenberg