A heliotrope (surveying instrument).

Concerning the sun.

(Greek mythology) The god of the Sun; son of Hyperion and Theia, brother of Selene and Eos, father of Phaeton amongst others. His Roman counterpart is Sol.

(historical) A sunroom or solarium of the Ancient Greeks.

plural of helio

(astronomy) Having the sun at the center/centre; usually in reference to a solar system or orbit. [from 17th c.]

(botany) A plant that turns so that it faces the sun. / (botany) Particularly, a purple-flowered plant of the species Heliotropium arborescens. / A light purple or violet colour.

Light purple or violet. / Keeping one’s face turned toward the sun.

A mechanical device, used in architecture, for demonstrating the sun's motion relative to a building.

(obsolete) A photograph representing an object in its natural colours.