Relating to or actuated by an impulse, rather than controlled by reason or careful deliberation.
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im·pul·sive im-'pəl-siv adj
1) having the power of or actually driving or impelling
2) actuated by or prone to act on impulse <\impulsive behavior>
3) acting momentarily <brief \impulsive auditory stimuli>
im·pul·sive·ly adv
im·pul·sive·ness n
Medical dictionary. 2011.