action potential


Definition of action potential

: a momentary reversal in electrical potential across a plasma membrane (as of a neuron or muscle fiber) that occurs when a cell has been activated by a stimulus

Examples of action potential in a Sentence

Recent Examples on the Web Huxley’s Nobel Prize winning work to understand the action potential - the basis for how neurons communicate with each other via discrete electrical impulses. Gabriel A. Silva, Forbes, 27 May 2021 Each neuron in the brain receives somewhere in the range of tens of thousands to hundreds of thousands of action potential electrical signals from other neurons that connect into it. Gabriel A. Silva, Forbes, 19 Apr. 2021 What’s the consequence of all the work required to generate an action potential in the postsynaptic neuron? Gabriel A. Silva, Forbes, 19 Apr. 2021 That may or may not result in a spike, or action potential, going out on the neuron’s axon to the dendrites of post-synaptic neurons. Quanta Magazine, 18 Feb. 2021 This was noteworthy because conventional action potentials are usually caused by sodium and potassium ions. Quanta Magazine, 14 Jan. 2020 Neurons firing action potentials that affect the downstream cells they are wired to (via synapses) are one type of mechanism, as are electronic circuits, made of transistors, capacitances, resistances and wires. Christof Koch, Scientific American, 1 Dec. 2019 Divide and Conquer The brain is a power-hungry organ; neurons are constantly sending each other information in the form of electrical pulses, known as spikes or action potentials. Quanta Magazine, 23 Aug. 2016

These example sentences are selected automatically from various online news sources to reflect current usage of the word 'action potential.' Views expressed in the examples do not represent the opinion of Merriam-Webster or its editors. Send us feedback.

See More

First Known Use of action potential

1913, in the meaning defined above

Keep scrolling for more

Learn More About action potential

Time Traveler for action potential

Time Traveler

The first known use of action potential was in 1913

See more words from the same year

Statistics for action potential

Last Updated

3 Jun 2021

Cite this Entry

“Action potential.” Dictionary, Merriam-Webster, Accessed 26 Jul. 2021.

Style: MLA
MLACheck Mark Icon ChicagoCheck Mark Icon APACheck Mark Icon Merriam-WebsterCheck Mark Icon

Keep scrolling for more

More Definitions for action potential

action potential


Medical Definition of action potential

: a momentary reversal in the potential difference across a plasma membrane (as of a nerve cell or muscle fiber) that occurs when a cell has been activated by a stimulus

called also spike potential

— compare resting potential — see afterpotential, generator potential, prepotential

More from Merriam-Webster on action potential Encyclopedia article about action potential


Test Your Vocabulary

Farm Idioms Quiz

  • cow coming home
  • What does 'poke' refer to in the expression 'pig in a poke'?
How Strong Is Your Vocabulary?

Test your vocabulary with our 10-question quiz!


Anagram puzzles meet word search.

Love words? Need even more definitions?

Subscribe to America's largest dictionary and get thousands more definitions and advanced search—ad free!