impetuous

adjective

1 she might live to regret this impetuous decision:

impulsive, rash, hasty, overhasty, reckless, heedless, foolhardy, incautious, imprudent, injudicious, ill-conceived, ill-considered, unplanned, unreasoned, unthought-out, unthinking;

spontaneous, impromptu, spur-of-the-moment, precipitate, precipitous, headlong, hurried, rushed.

▷antonyms cautious, considered.

2 an impetuous flow of water:

torrential, powerful, forceful, vigorous, violent, raging, rampant, relentless, unrestrained, uncontrolled, unbridled;

rapid, fast, fast-flowing, rushing.

▷antonyms sluggish, weak.

choose the right word

impetuous, impulsive, precipitate, headlong

These words all refer to haste and lack of forethought.

■ Impetuous and impulsive are very similar in meaning, applying to people, their characters, or their actions, but impetuous emphasizes the irresponsibility involved (I was a bit impetuous offering him the job just like that | she might live to regret this impetuous decision), while to be impulsive can be endearing (an act of impulsive generosity | they married as young, impulsive teenagers).

■ Precipitate is used of actions, not people; a precipitate act is typically undesirable and lacks proper planning or consideration of its possible effect (the danger of inappropriate and precipitate intervention which fails to protect the child).

■ When used as an adjective, headlong applies only to actions, not to people. It describes actions which, after their initial impetus, are not guided by any plan and quickly get out of control (our headlong rush to develop and industrialize the world). As an adverb, headlong can also apply to people in this sense (I'm going to enjoy each day while it lasts, instead of dashing headlong into the future).