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siderostat

[ sid-er-uh-stat ]
/ ˈsɪd ər əˌstæt /

noun

a telescopic device for reflecting the light of a star in a constant direction, the chief component of which is a plane mirror turned by a clock mechanism to correct for the rotation of the earth.

Words nearby siderostat

siderophilous, siderophore, sideroscope, siderosilicosis, siderosis, siderostat, siderotic, siderotic nodules, sidesaddle, sidesaddle flower, sideshow

Origin of siderostat

First recorded in 1875–80; sidero-2 + -stat

OTHER WORDS FROM siderostat

sid·er·o·stat·ic, adjective
Dictionary.com Unabridged Based on the Random House Unabridged Dictionary, © Random House, Inc. 2019

Examples from the Web for siderostat

  • The movable portion of the roof of the building had been slid back, and the mirror of the siderostat stood bared to the sky.

    The Romance of Modern Invention|Archibald Williams

  • The siderostat, twenty-seven feet high, and as many in length, weighed forty-five tons.

    The Romance of Modern Invention|Archibald Williams

  • The telescope was housed at the Exhibition in a long gallery pointing due north and south, the siderostat at the north end.

    The Romance of Modern Invention|Archibald Williams

British Dictionary definitions for siderostat

siderostat
/ (ˈsaɪdərəʊˌstæt) /

noun

an astronomical instrument consisting essentially of a plane mirror driven about two axes so that light from a celestial body, esp the sun, is reflected along a constant direction for a long period of timeSee also heliostat Compare coelostat

Derived forms of siderostat

siderostatic, adjective

Word Origin for siderostat

C19: from sidero-, from Latin sidus a star + -stat, on the model of heliostat
Collins English Dictionary - Complete & Unabridged 2012 Digital Edition © William Collins Sons & Co. Ltd. 1979, 1986 © HarperCollins Publishers 1998, 2000, 2003, 2005, 2006, 2007, 2009, 2012