im·pet·u·ous
adjective \im-ˈpech-wəs; –ˈpe-chə-, -chü-əs\
: acting or done quickly and without thought : controlled by emotion rather than thought
1: marked by impulsive vehemence or passion <an impetuous temperament>
2: marked by force and violence of movement or action <an impetuous wind>
— im·pet·u·ous·ly adverb
— im·pet·u·ous·ness noun
Definition source: http://www.merriam-webster.com
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