a. [f. Gr. ἀφ’ = ἀπό from + ἤλιος sun + τροπικός belonging to turning: see -TROPIC.] Bending or turning away from the sun: said of leaves, and other parts of plants.
1880. Darwin, Movem. Plants, 552. The sub-aërial roots observed by Wiesner were all apheliotropic.
1882. F. Darwin in Nature, 27 April, 600/1. The light … causing apheliotropic movement in the leaves.
