Synonyms/Hypernyms (Ordered by Estimated Frequency) of noun tropism

1 sense of tropism

Sense 1
tropism -- (an involuntary orienting response; positive or negative reaction to a stimulus source)
       => reaction, response -- (a bodily process occurring due to the effect of some antecedent stimulus or agent; "a bad reaction to the medicine"; "his responses have slowed with age")