'Heliostat' definitions:
Definition of 'Heliostat'
From: GCIDE
- Heliostat \He"li*o*stat\, n. [Helio- + Gr. ? placed, standing, fr. ? to place, stand: cf. F. h['e]liostate.] An instrument consisting of a mirror moved by clockwork, by which a sunbeam is made apparently stationary, by being steadily directed to one spot during the whole of its diurnal period; also, a geodetic heliotrope. [1913 Webster]
Definition of 'heliostat'
From: GCIDE
- Siderostat \Sid"er*o*stat\, n. [L. sidus, sideris, a star + Gr. ??? standing, fixed, fr. ???? to place.] (Astron.) An apparatus consisting essentially of a mirror moved by clockwork so as to throw the rays of the sun or a star in a fixed direction; -- a more general term for heliostat. [1913 Webster]