impulse

impulse — noun

1. A sudden, strong feeling of wanting to do something, often without thinking care

1.nounB1
Definition

A sudden, strong feeling of wanting to do something, often without thinking carefully about the results or possible problems.

Example

Noor felt a sudden impulse to jump into the lake with her clothes on.

impulse + to-infinitive for sudden desire

Minho resisted the impulse to check his phone during the meeting.

resist the impulse to [verb]

Common collocations
  • resist an impulse
  • act on impulse
  • sudden impulse
  • overwhelming impulse
  • impulse buy
Synonyms
  • urge

    A strong desire that you feel inside; 'urge' suggests a more physical or emotional pressure than 'impulse'.

  • whim

    A sudden but often short-lived or less serious desire; 'whim' sounds lighter than 'impulse'.

  • compulsion

    A very strong, hard-to-resist desire, often linked to anxiety or habit rather than a momentary thought.

Antonyms
  • deliberation

    Careful thought before acting, the opposite of acting without planning.

  • plan

    A decision made in advance, the opposite of a sudden unplanned wish.

Grammar Patterns

impulse + to-infinitive

on impulse (adverbial phrase)

Usage Note

The phrase 'on impulse' means doing something suddenly without planning. An 'impulse buy' or 'impulse purchase' refers to an unplanned item bought at the counter. 'Impulse control' is the ability to resist sudden desires.

Common Mistakes

He had an impulse of buying a new phone.
He had an impulse to buy a new phone.
'impulse' takes a to-infinitive, not 'of + gerund'.
I did it by impulse.
I did it on impulse.
The correct preposition is 'on', not 'by'.

2. A short electrical or chemical signal that travels through a nerve, wire, or oth

2.nounB2
Definition

A short electrical or chemical signal that travels through a nerve, wire, or other pathway, carrying information from one part of a body or machine to another.

Example

The nerve impulse travelled from Mateo's fingertip to his brain in a split second.

nerve impulse — biological / medical context

An electrical impulse from the pacemaker kept the patient's heart beating steadily.

electrical impulse in medical device context

Common collocations
  • nerve impulse
  • electrical impulse
  • light impulse
  • chemical impulse
  • carry an impulse
  • transmit an impulse
Synonyms
  • signal

    A broader term; 'signal' can be any transmitted message, while 'impulse' implies a short, sharp burst.

  • pulse

    Overlaps with 'impulse' in electronics, but 'pulse' is more common for energy bursts and heartbeat; 'impulse' emphasizes the single brief event.

Grammar Patterns

nerve impulse

electrical impulse

Usage Note

Common in biology, medicine, and electronics. In anatomy, 'nerve impulse' is the electrical message moving through a neuron. In electronics, 'electrical impulse' or 'pulse' is a brief signal sent through a circuit. Do not confuse with 'pulse', which refers to the physical beating of the heart.

Common Mistakes

The doctor measured his nerve impulses at the wrist.
The doctor took his pulse at the wrist.
For heartbeat rhythm, use 'pulse'; 'nerve impulses' are electrical signals in the nervous system, not blood flow.

3. A strong force or influence that causes something to happen, develop, or make pr

3.nounB2
Definition

A strong force or influence that causes something to happen, develop, or make progress.

Example

The desire for fairness was the main impulse behind the new school policy.

impulse behind [something] — cause/reason pattern

Ada's creative impulse pushed her to leave her office job and become a full-time potter.

creative impulse — abstract motivation collocation

Common collocations
  • creative impulse
  • main impulse
  • reform impulse
  • political impulse
  • charitable impulse
  • impulse behind
  • impulse toward
Synonyms
  • impetus

    Almost identical in meaning but more formal; 'impetus' is very common in academic writing for 'a force that starts a process'.

  • motivation

    Broader and more personal; 'motivation' refers to the internal reasons a person has, while 'impulse' suggests an outward-driving energy.

  • stimulus

    Often used in economics or psychology; 'stimulus' is an external factor that causes a reaction, whereas 'impulse' can be internal.

Antonyms
  • deterrent

    Something that discourages action or progress.

  • obstacle

    A barrier that slows or stops a forward movement or development.

Grammar Patterns

impulse behind [something]

main/creative/political impulse

Usage Note

This sense is common in formal, academic, and journalistic writing. It describes the underlying motivation of a movement, policy, or change. The 'impulse' is often followed by 'behind' or 'toward' to name the goal. Unlike sense 1, this is not about a momentary urge but a sustained driving energy.

Common Mistakes

He had an impulse behind studying harder.
His main impulse was to get into a good university.
'Impulse behind' is used with abstract movements or policies, not personal daily goals. For personal motivation, use 'reason' or 'motive'.
Idioms

on impulse

idiom

Without previous thought or planning; because of a sudden, unplanned wish.

Jessica picked up the vintage lamp on impulse at a flea market and later wished she had checked the price first.

Most shoppers who buy items near the register do so on impulse rather than by plan.

impulse buy / impulse purchase / impulse buying

idiom

The act of buying something because you suddenly want it, not because you needed or planned to buy it.

The small toys near the checkout counter are placed there to encourage impulse buying.

Amelia regretted her impulse purchase of a third pair of running shoes the moment she got home.

impulse control

idiom

The ability to stop yourself from doing something you suddenly want to do, especially when the desire could lead to a problem.

Eli's impulse control improved a lot after he started practising mindfulness every morning.

Children usually have weaker impulse control than adults, which is why they grab things without asking.

impulse — verb

Word family

Synonym discussion

Sense: noun/1

All three words describe a sudden desire to do something, but they differ in strength, duration, and context. 'Impulse' is the strongest and most sudden — an impulse can make you act without thinking at all. 'Urge' is a strong desire that you may be aware of before acting; it often feels like a pressure building inside you. 'Whim' is the weakest and most short-lived — a whim is a passing fancy that changes easily. For example: 'On an impulse, she quit her job that morning' suggests a sudden, unplanned decision. 'He felt an urge to call his mother but waited until evening' points to a strong but controllable feeling. 'I bought the hat on a whim but returned it the next day' indicates a light, temporary fancy. 'Impulse' also has technical uses (nerve impulse, electrical impulse) that 'urge' and 'whim' do not share.

urge ↗whim ↗impulse ↗

Common collocations

Nouns

Adverbs

Phrases

Prepositions

Etymology

LatinFrenchEnglish

From Latin 'impulsus', meaning 'a push against, a striking upon', which comes from 'impellere' (to push against, to drive forward). The sense of a sudden mental urge emerged in the 1600s, and the technical meaning of an electrical signal developed with modern science in the 1800s.