noun
An answer
Reactions to stimuli include: contraction, expansion, dilation, constriction, jerk, knee jerk, tropism, heliotropism, phototropism, cognition, shock, exhaustion, stupor, anger, disgust, revulsion, fear, joy, laughter, wonder.
A backward tendency, especially in politics
See reaction in Webster's New World Roget's A-Z Thesaurus II
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