Pronunciation: (im-pech'OO-us), [key]
1. of, pertaining to, or characterized by sudden or rash action, emotion, etc.; impulsive: an impetuous decision; an impetuous person.
2. having great impetus; moving with great force; violent: the impetuous winds.
Random House Unabridged Dictionary, Copyright © 1997, by Random House, Inc., on Infoplease.