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
Recent Examples on the Web But the mechanism by which oxybenzone could harm corals wasn't clear. John Timmer, Ars Technica, 8 May 2022 In the case of Russia, the mechanism of repression is fairly self-evident. Laura Beers, CNN, 6 May 2022 When a release mechanism is unlatched, the device launches into the air. Margaret Osborne, Smithsonian Magazine, 2 May 2022 This basic mechanism is similar to the one members of the animal kingdom use. Sophie Bushwick, Scientific American, 27 Apr. 2022 The throttling mechanism will be currency mismatch, meaning the accumulation of assets or liabilities in one currency when the things that matter to a company (revenues, book value or the like) are denominated in another. Joseph C. Sternberg, WSJ, 21 Apr. 2022 Another mechanism is to develop metrics and reporting mechanisms perhaps by auditors in conjunction with school districts or boards to evaluate the number of students served and in what capacity to evaluate good program successes. Jamie Goldberg, oregonlive, 19 Apr. 2022 That locking mechanism is at the heart of the bike’s fault, though, as Fiido had received a report of a frame defect that can see the bike break in half. Mark Knapp, PCMAG, 14 Apr. 2022 The mechanism by which this leads to remdesivir resistance is not immediately evident. William A. Haseltine, Forbes, 13 Apr. 2022 See More

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.

First Known Use of mechanism

1662, in the meaning defined at sense 1a

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Time Traveler for mechanism

Time Traveler

The first known use of mechanism was in 1662

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Dictionary Entries Near mechanism

mechanics' institute



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Last Updated

15 May 2022

Cite this Entry

“Mechanism.” Dictionary, Merriam-Webster, Accessed 22 May. 2022.

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More Definitions for mechanism


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


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