paraheliotropism
/ˌparəhiːlɪə(ʊ)ˈtrəʊpɪz(ə)m/ /ˌparəhiːlɪˈɒtrəpɪz(ə)m/Botany
noun
A type of tropism in which a plant's leaves move to reduce injuriously intense illumination, usually by keeping their blades parallel to the light rays.
Origin
Late 19th century; earliest use found in Charles Darwin (1809–1882), naturalist, geologist, and originator of the theory of natural selection. From para- + heliotropism, probably after paraheliotropic.