epinasty

noun

epi·​nas·​ty ˈe-pə-ˌna-stē 

: a nastic movement in which a plant part (such as a flower petal) is bent outward and often downward

Word History

Etymology

borrowed from German Epinastie, from epinastisch "displaying epinasty" (from epi- epi- + Greek nastós "close-pressed, firm" + -isch -ish) + -ie -y;2; nastós, verbal adjective of nássein (Attic náttein) "to pile up densely, pack," of obscure origin

Note: The term epinastisch—as well as the corresponding terms hyponastisch and diplonastisch—were apparently introduced in a communication to the thirty-first annual meeting of the Gesellschaft Deutscher Naturforscher und Ärzte (Society of German Naturalists and Physicians) by the botanist Karl Friedrich Schimper (1803-67) (Amtlicher Bericht über die einunddreissigste Versammlung Deutscher Naturforscher und Ärzte zu Göttingen im September 1854 [Göttingen, 1860], p. 87).

First Known Use

1880, in the meaning defined above