Heliostat

[hi:liәstæt]

Definition

(n.) 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.

Checked by Gregory

Definition

n. an instrument by means of which a beam of sunlight is reflected in an invariable direction.

Inputed by Logan