a. [ Gr. &unr_; + &unr_; sun + &unr_; belonging to a turning. ] Turning away from the sun; -- said of leaves, etc. Darwin. [ 1913 Webster ]

n. The habit of bending from the sunlight; -- said of certain plants. [ 1913 Webster ]

a. [ Gr. &unr_; through, at variance + &unr_; sun + &unr_; turning. ] (Bot.) Relating or, or manifesting, diaheliotropism. [ 1913 Webster ]

n. (Bot.) A tendency of leaves or other organs of plants to have their dorsal surface faced towards the rays of light. [ 1913 Webster ]

n. [ F. héliotrope, L. heliotropium, Gr. &unr_;; &unr_; the sun + &unr_; to turn, &unr_; turn. See Heliacal, Trope. ] 1. (Anc. Astron.) An instrument or machine for showing when the sun arrived at the tropics and equinoctial line. [ 1913 Webster ]

2. (Bot.) A plant of the genus Heliotropium; -- called also turnsole and girasole. Heliotropium Peruvianum is the commonly cultivated species with fragrant flowers. [ 1913 Webster ]

3. (Geodesy & Signal Service) An instrument for making signals to an observer at a distance, by means of the sun's rays thrown from a mirror. [ 1913 Webster ]

4. (Min.) See Bloodstone (a). [ 1913 Webster ]

Heliotrope purple, a grayish purple color. [ 1913 Webster ]

n. The person at a geodetic station who has charge of the heliotrope. [ 1913 Webster ]

a. (Bot.) Manifesting heliotropism; turning toward the sun. [ 1913 Webster ]

n. [ Helio- + Gr. &unr_; to turn. ] (Bot.) The phenomenon of turning toward the light, seen in many leaves and flowers. [ 1913 Webster ]

n. [ Helio- + -type. ] A picture obtained by the process of heliotypy. [ 1913 Webster ]

a. Relating to, or obtained by, heliotypy. [ 1913 Webster ]

n. A method of transferring pictures from photographic negatives to hardened gelatin plates from which impressions are produced on paper as by lithography. [ 1913 Webster ]