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impulsive

[im-puhl-siv]
adjective
  1. actuated or swayed by emotional or involuntary impulses: an impulsive child.
  2. having the power or effect of impelling; characterized by impulsion: impulsive forces.
  3. inciting to action: the impulsive effects of a revolutionary idea.
  4. Mechanics. (of forces) acting momentarily; not continuous.

Origin of impulsive

1375–1425 for an earlier sense; 1545–55 for current senses; late Middle English impulsif < Medieval Latin impulsīvus. See impulse, -ive
Related formsim·pul·sive·ly, adverbim·pul·sive·ness, im·pul·siv·i·ty, nounnon·im·pul·sive, adjectivenon·im·pul·sive·ly, adverbnon·im·pul·sive·ness, nounun·im·pul·sive, adjectiveun·im·pul·sive·ly, adverb
Can be confusedcompulsive impulsive impetuous (see synonym study at impetuous)

Synonyms for impulsive

1. rash, quick, hasty. See impetuous.
Dictionary.com Unabridged Based on the Random House Unabridged Dictionary, © Random House, Inc. 2018

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British Dictionary definitions for impulsivity

impulsive

adjective
  1. characterized by actions based on sudden desires, whims, or inclinations rather than careful thoughtan impulsive man
  2. based on emotional impulses or whims; spontaneousan impulsive kiss
  3. forceful, inciting, or impelling
  4. (of physical forces) acting for a short time; not continuous
  5. (of a sound) brief, loud, and having a wide frequency range
Derived Formsimpulsively, adverbimpulsiveness, noun
Collins English Dictionary - Complete & Unabridged 2012 Digital Edition © William Collins Sons & Co. Ltd. 1979, 1986 © HarperCollins Publishers 1998, 2000, 2003, 2005, 2006, 2007, 2009, 2012
Word Origin and History for impulsivity
n.

1891; see impulsive + -ity.

impulsive

adj.

early 15c., originally in reference to medicine that reduces swelling or humors, from Middle French impulsif or directly from Medieval Latin impulsivus, from Latin impuls-, past participle stem of impellere (see impel). Of persons, "rash, characterized by impulses," from 1847.

Online Etymology Dictionary, © 2010 Douglas Harper
impulsivity in Medicine

impulsive

[ĭm-pŭl′sĭv]
adj.
  1. Inclined or tending to act on impulse rather than thought.
  2. Motivated by or resulting from impulse.
Related formsim•pul′sive•ness null n.
The American Heritage® Stedman's Medical Dictionary Copyright © 2002, 2001, 1995 by Houghton Mifflin Company. Published by Houghton Mifflin Company.