impulse

American  

[im-puhls] / ˈɪm pʌls /

noun

1. the influence of a particular feeling, mental state, etc..

   to act under a generous impulse; to strike out at someone from an angry impulse.

2. sudden, involuntary inclination prompting to action.

   to be swayed by impulse.

3. an instance of this.

4. a psychic drive or instinctual urge.

5. an impelling action or force, driving onward or inducing motion.

6. the effect of an impelling force; motion induced; impetus given.

7. Physiology. a progressive wave of excitation over a nerve or muscle fiber, having either a stimulating or inhibitory effect.

8. Mechanics. the product of the average force acting upon a body and the time during which it acts, equivalent to the change in the momentum of the body produced by such a force.

9. Electricity. a single, usually sudden, flow of current in one direction.

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adjective

1. marked by or acting on impulse.

   an impulse buyer.

2. bought or acquired on impulse.

   To reduce expenses, shun impulse items when shopping.

impulse British  

/ ˈɪmpʌls /

noun

1. an impelling force or motion; thrust; impetus

2. a sudden desire, whim, or inclination

   I bought it on an impulse

3. an instinctive drive; urge

4. tendency; current; trend

5. physics

   1. the product of the average magnitude of a force acting on a body and the time for which it acts

   2. the change in the momentum of a body as a result of a force acting upon it for a short period of time

6. physiol See nerve impulse

7. electronics a less common word for pulse 1

8. spontaneously or impulsively

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impulse Scientific  

/ ĭm′pŭls′ /

1. A sudden flow of electrical current in one direction.

2. An electrical signal traveling along the axon of a neuron. Nerve impulses excite or inhibit activity in other neurons or in the tissues of the body, such as muscles and glands.

3. The change of momentum of a body or physical system over a time interval in classical mechanics, equal to the force applied times the length of the time interval over which it is applied.

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Etymology

Origin of impulse

First recorded in 1640–50; from Latin impulsus “incitement, pressure,” noun use of past participle of impellere “to strike against, set in motion”; impel

Example Sentences

Those email promos are too good at winning over consumers — 72% of online shoppers have made an impulse purchase after seeing an advertised discount, according to Capital One Shopping.

From MarketWatch • Mar. 31, 2026

Caesar, Hegel writes, was driven by “an unconscious impulse that occasioned the accomplishment of that for which the time was ripe.”

From Salon • Mar. 28, 2026

It is an "under-estimate" to say impulse control disorders affect fewer than 1% of patients in drug leaflets, according to Valerie Voon, who was one of the authors of the 2010 study.

From BBC • Mar. 28, 2026

Yet in this dense marketplace of ideas, identities and impulse buys, a shared sensibility quickly comes into focus.

From Barron's • Mar. 28, 2026

Yet, as he hurried off down the dark, murmuring street, she had a sudden impulse to call him back, to ask him to take her with him and never let her go again.

From "Go Tell It on the Mountain" by James Baldwin

Related Words

• desire
• feeling
• inclination
• influence
• instinct
• motivation
• motive
• notion
• passion
• thought
• whim
• wish