Bot. [f. as prec. + -ISM.] The property possessed by growing plant-organs of turning or bending towards (positive thermotropism) or away from (negative thermotropism) the sun or other source of heat. In Biology, The bending or growth of any organism dependent upon temperature (Cent. Dict., Suppl.).
1898. trans. Strasburger’s Text-Bk. Bot., I. ii. 263. Thermotropism … and Aerotropism … stand in direct relations to certain vital requirements of plants.
