mech·​a·​nism | \ ˈme-kə-ˌni-zəm How to pronounce mechanism (audio) \

Definition of mechanism

1a : a piece of machinery (see machinery sense 1) The camera's shutter mechanism is broken.
b : a process, technique, or system for achieving a result the mechanisms of peace— F. D. Roosevelt
2 : mechanical operation or action : working sense 2 he acknowledges nothing besides matter and motion; so that all must be performed either by mechanism or by accident— Richard Bentley
3 : a doctrine that holds natural processes (as of life) to be mechanically determined and capable of complete explanation by the laws of physics and chemistry
4 : the fundamental processes involved in or responsible for an action, reaction, or other natural phenomenon meteorologists believe that this pressure jump is the mechanism responsible for storms and tornadoesThink — compare defense mechanism

Examples of mechanism in a Sentence

The camera's shutter mechanism is broken. Scientists are studying the body's mechanisms for controlling weight. There is no mechanism in place for enforcing the new law. a legal mechanism to prevent lobbyists from exerting unfair influence psychological mechanisms for dealing with a tragic loss
See More
Recent Examples on the Web Easy to open and close legs, even with their locking mechanism. Sian Babish,, "The best indoor folding table," 29 Mar. 2021 The technicians identified the unexploded ordnance as a live cannonball round used during the Civil War and determined its fusing mechanism was still intact, the state's Office of the State Fire Marshal (OSFM) said in a statement on Tuesday. Alaa Elassar, CNN, "Bomb squad safely detonates Civil War cannonball found in Maryland," 28 Mar. 2021 Her coping mechanism involves going to bars, feigning drunkenness, and waiting for opportunistic men to take her home. Radhika Seth, Vogue, "Carey Mulligan and Emerald Fennell on Promising Young Woman and the Concept Female Bodies as ‘Something to Be Won’," 26 Mar. 2021 Simply connect your Twitter account to your deletion mechanism of choice and follow its instructions. Eric Limer, Popular Mechanics, "You Should Probably Delete All of Your Old Tweets. Here's How to Do It.," 17 Mar. 2021 The flee-or-fight response was their main mechanism to achieve their biological mandates. Luis E. Romero, Forbes, "Jurassic Leadership And The Dinosaur Within Us," 25 Feb. 2021 The body produces interferon beta to fight off viral infections, but the new coronavirus appears to suppress production of the proteins as part of its mechanism to evade patients' immune responses, BBC News reports. TheWeek, "U.K. begins large trial of new COVID-19 treatment inhaled into the lungs," 13 Jan. 2021 But when these clunky needles were considered cutting-edge science, mosquitoes had already been plunging their blood-sucking mechanism into animals for millions of years. Leslie Nemo, Scientific American, "Mosquitoes Stab Animals with a Syringelike Proboscis," 8 Jan. 2021 Sparking a participatory dynamic with the right message and delivery mechanism is essential. Aaron Fletcher, Rolling Stone, "How Brands Can Engage Gamers by Understanding the Esports Community," 11 Mar. 2021

These example sentences are selected automatically from various online news sources to reflect current usage of the word 'mechanism.' 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 mechanism

1662, in the meaning defined at sense 1a

Keep scrolling for more

Learn More about mechanism

Time Traveler for mechanism

Time Traveler

The first known use of mechanism was in 1662

See more words from the same year

Statistics for mechanism

Last Updated

9 Apr 2021

Cite this Entry

“Mechanism.” Dictionary, Merriam-Webster, Accessed 13 Apr. 2021.

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

Keep scrolling for more

More Definitions for mechanism



English Language Learners Definition of mechanism

: a piece of machinery : a mechanical part or group of parts having a particular function
: a process or system that is used to produce a particular result
: a way of acting, thinking, or behaving that helps or protects a person in a specified way


mech·​a·​nism | \ ˈme-kə-ˌni-zəm How to pronounce mechanism (audio) \

Kids Definition of mechanism

1 : a piece of machinery
2 : the parts by which a machine operates the mechanism of a watch
3 : the parts or steps that make up a process or activity the mechanism of government


mech·​a·​nism | \ ˈmek-ə-ˌniz-əm How to pronounce mechanism (audio) \

Medical Definition of mechanism

1 : a piece of machinery
2a : a bodily process or function the mechanism of healing
b : the combination of mental processes by which a result is obtained psychological mechanisms
3 : the fundamental physical or chemical processes involved in or responsible for an action, reaction, or other natural phenomenon

Other Words from mechanism

mechanistic \ ˌmek-​ə-​ˈnis-​tik How to pronounce mechanism (audio) \ adjective

Keep scrolling for more

Comments on mechanism

What made you want to look up mechanism? Please tell us where you read or heard it (including the quote, if possible).


Test Your Vocabulary

The Exceptions Quiz III

  • one green toy robot amidst many red toy robots
  • Which of these words does not mean "nonsense"?
How Strong Is Your Vocabulary?

Test your vocabulary with our 10-question quiz!

Universal Daily Crossword

A daily challenge for crossword fanatics.

Love words? Need even more definitions?

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