Definition of impulse in English:

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Pronunciation: /ˈɪmpʌls/


1A sudden strong and unreflective urge or desire to act: I had an almost irresistible impulse to giggle
More example sentences
  • Bergman wants to portray the powerful, often destructive desires and impulses lying beneath placid social exteriors.
  • I had a sudden impulse to tell the woman pouring the wine that I loved her.
  • Driven by a mad impulse, I strolled up to the road in front of the cab, and stood before it.
urge, instinct, drive, compulsion, need, itch;
whim, caprice, desire, fancy, notion
1.1 [mass noun] The tendency to act impulsively: he was a man of impulse, not premeditation
spontaneity, impetuosity, wildness, recklessness, irresponsibility, rashness
2Something that causes something to happen or happen more quickly; an impetus: an added impulse to this process of renewal
More example sentences
  • Even so, in this process the educated must provide the initial impulse; they must make the masses conscious of themselves and of their destiny.
  • The individual provides the impulse which sets the process of litigation in motion, but the institution - the law - defines the terms.
  • One of the main impulses for devolution in the 1980s and 1990s was the need to defend the social democratic settlement in Scotland and Wales from the neo-liberal attack.
inspiration, stimulation, stimulus, incitement, motivation, encouragement, fillip, spur, prod, catalyst
3A pulse of electrical energy; a brief current: nerve impulses electrical impulses
More example sentences
  • Implanted osteogenic stimulators deliver electrical impulses directly to the site where bone regrowth needs to occur.
  • Unlike its electrical predecessor, an optical switch does not convert the signal to an electrical impulse before directing it.
  • Using this device he was able to show that the currents traveling through nerves and muscles were in the form of small, brief electrical impulses that we now call action potentials.
pulse, current, wave;
signal, message, brainwave, communication
4 Physics A force acting briefly on a body and producing a finite change of momentum: ability to communicate motion by impulse
More example sentences
  • This will open the door for the realization that man exists within a huge field of gravitational and magnetic impulses.
  • The process of minimizing an impact force can be approached from the definition of the impulse of force.
  • This hypothesis has been around for decades and the study of it has failed to generate enough positive data to lead us to believe that sound waves instead of ion flux is how impulses are generated.
4.1A change of momentum produced by an impulse, equivalent to the average value of the force multiplied by the time during which it acts.
Example sentences
  • The average force and impulse of impact was found to be 1025 N and 11.0 N / s, respectively.
  • The impulse had a value of 1, and the highest peak in the response is less than 0.25, falling rapidly to tiny values.
  • Specific impulse equals thrust multiplied by the time over which the thrust acts.


on impulse (or on an impulse)

Suddenly and without forethought; impulsively: on an impulse he returned to the bar she acted purely on impulse
More example sentences
  • He had health worries and was short of money but had acted on impulse to provide the children with something he had promised them.
  • Before you are allowed to place a bet there is a message asking you to confirm your bet so you are less likely to act on impulse.
  • I wonder if he really did act on an impulse, or if there's more to it?
impulsively, spontaneously, on the spur of the moment, without forethought, without planning, without thinking twice, without premeditation, unpremeditatedly


Early 17th century (as a verb in the sense 'give an impulse to'): the verb from Latin impuls- 'driven on', the noun from impulsus 'impulsion', both from the verb impellere (see impel).

For editors and proofreaders

Line breaks: im|pulse

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