sundial

An instrument that indicates local apparent solar time by the shadow cast by a central projecting pointer on a surrounding calibrated dial.

An instrument for indicating the time of day by means of the position of a shadow on a dial or diagram.

An instrument to show the time of day by means of the shadow of a gnomon, or style, on a plate.

Any shell of the genus Solarium. See Solarium.

A simple timekeeping device in which the shadow cast by a vertical pole or plate (the gnomon) is used to indicate the time of day.