impulse

[ im-puhls ]
See synonyms for: impulseimpulses on Thesaurus.com

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.

  1. an instance of this.

  2. a psychic drive or instinctual urge.

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

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

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

  6. 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.

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

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.

Origin of impulse

1
First recorded in 1640–50; from Latin impulsus “incitement, pressure,” noun use of past participle of impellere “to strike against, set in motion”; see impel

Words Nearby impulse

Dictionary.com Unabridged Based on the Random House Unabridged Dictionary, © Random House, Inc. 2024

How to use impulse in a sentence

British Dictionary definitions for impulse

impulse

/ (ˈɪmpʌls) /


noun
  1. an impelling force or motion; thrust; impetus

  2. a sudden desire, whim, or inclination: I bought it on an impulse

  1. an instinctive drive; urge

  2. tendency; current; trend

  3. physics

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

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

  4. physiol See nerve impulse

  5. electronics a less common word for pulse 1 (def. 2)

  6. on impulse spontaneously or impulsively

Origin of impulse

1
C17: from Latin impulsus a pushing against, incitement, from impellere to strike against; see impel

Collins English Dictionary - Complete & Unabridged 2012 Digital Edition © William Collins Sons & Co. Ltd. 1979, 1986 © HarperCollins Publishers 1998, 2000, 2003, 2005, 2006, 2007, 2009, 2012

Scientific definitions for impulse

impulse

[ ĭmpŭls′ ]


  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.

  1. 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.

The American Heritage® Science Dictionary Copyright © 2011. Published by Houghton Mifflin Harcourt Publishing Company. All rights reserved.