mech·a·nism | \ˈme-kə-ˌni-zəm \

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
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Recent Examples on the Web

Gagliano built a mechanism that would abruptly drop the plants by about a foot without harming them. Katia Moskvitch, WIRED, "Slime Molds Remember—But Do They Learn?," 14 July 2018 The nuclear option would be for WTO members to invoke Article 9, which allows voting where consensus isn’t possible, thereby providing a mechanism to override the U.S. veto. Simon Nixon, WSJ, "Trump Puts the WTO on the Ropes," 11 July 2018 The 500-strong lower house would be chosen by a new electoral mechanism likely to produce a weak coalition government, giving the generals final say on key policy decisions. Time, "Exclusive: Thailand PM Prayuth Chan-ocha on Turning to China Over the U.S.," 21 June 2018 The US Patent Office recently made a similar mechanism available. Timothy B. Lee, Ars Technica, "Inventor says Google is patenting work he put in the public domain," 10 June 2018 As in certain films by Pedro Almodovar (whom the sisters cite as an influence), humor seems like a coping mechanism in the face of material that might be too difficult to approach seriously. Ben Sachs, Chicago Reader, "Chicago Underground Film Festival: The Story of a Satellite," 6 June 2018 The Brookfield Common Council on Tuesday, June 5, approved a financing mechanism to buy 9.5 acres for the center and hotel. Darryl Enriquez, Milwaukee Journal Sentinel, "Demolition underway at Sears store in Brookfield Square; BistroPlex, hotel, bumper cars will take its place," 6 June 2018 Šikšnys first showed that the CRISPR-Cas9 system, a bacterial immune mechanism, could be transferred from one bacterium to another. Jon Cohen, Science | AAAS, "With prestigious prize, an overshadowed CRISPR researcher wins the spotlight," 4 June 2018 When cats fall, a mechanism in their inner ear causes their head, neck, and backbone to rotate into a position that will help them land on their feet. National Geographic, "Would Your Cat Choose You Over Its Food?," 19 May 2018

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.

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First Known Use of mechanism

1662, in the meaning defined at sense 1a

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Phrases Related to mechanism

survival mechanism

Statistics for mechanism

Last Updated

8 Oct 2018

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Time Traveler for mechanism

The first known use of mechanism was in 1662

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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 \

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 \

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 \ adjective

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Comments on mechanism

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lying above or upon

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