Word Study
tropism
CIDE DICTIONARY
tropism, n. [Gr. troph` a turning, tre`pein to turn + -ism.].
Modification of the direction of growth, caused by some external influence, such as light; -- sometimes used for motion of an organism toward or away from an external stimulus, more properly called taxis . [Webster 1913 Suppl.]
OXFORD DICTIONARY
tropism, n. Biol. the turning of all or part of an organism in a particular direction in response to an external stimulus.
Etymology
Gk tropos turning f. trepo turn
THESAURUS
tropism
a thing for, affinity, aptitude, aptness, bent, bias, cast, conatus, conduciveness, delight, diathesis, disposition, eagerness, feeling for, inclination, leaning, liability, liking, penchant, predilection, predisposition, prejudice, probability, proclivity, proneness, propensity, readiness, sensitivity to, soft spot, susceptibility, tendency, turn, twist, warp, weakness, willingnessFor further exploring for "tropism" in Webster Dictionary Online