noun sid·er·o·stat \ˈsidərəˌstat\

Definition of siderostat



  1. :  an equatorially mounted mirror moved by clockwork to reflect the rays of a celestial body observed in a constant usually horizontal direction — compare heliostat

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Origin and Etymology of siderostat

International Scientific Vocabulary 2sidero- + -stat

Seen and Heard

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to cast off or become cast off

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