mechanism

noun

mech·​a·​nism ˈme-kə-ˌni-zəm How to pronounce mechanism (audio)
1
a
: 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 peaceF. 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 accidentRichard 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
Examples are automatically compiled from online sources to show current usage. Read More Opinions expressed in the examples do not represent those of Merriam-Webster or its editors. Send us feedback.
At a minimum, effective infrastructure includes robust reporting mechanisms, swift response protocols, and consistent accountability measures - regardless of sector and size of organizations. Aparna Rae, Forbes.com, 6 June 2025 Trump was under particular pressure from American auto suppliers, who wrote a letter decrying Chinese export controls, particularly the rare-earth magnets that are essential to key components including brakes and steering mechanisms — as well as semiconductors used in smartphones and laptops. Michael Barclay, Quartz, 6 June 2025 Most of this carnivorous botany is small, but the diversity of different trapping mechanisms raises an evolutionary question. Riley Black, Smithsonian Magazine, 6 June 2025 Without any clear enforcement mechanism, companies that use dyes in food could go through the motions with the administration while continuing to use dyes in perpetuity. Andrea Ruth, The Washington Examiner, 6 June 2025 See All Example Sentences for mechanism

Word History

First Known Use

1662, in the meaning defined at sense 1a

Time Traveler
The first known use of mechanism was in 1662

Browse Nearby Words

Cite this Entry

“Mechanism.” Merriam-Webster.com Dictionary, Merriam-Webster, https://www.merriam-webster.com/dictionary/mechanism. Accessed 11 Jun. 2025.

Kids Definition

mechanism

noun
mech·​a·​nism ˈmek-ə-ˌniz-əm How to pronounce mechanism (audio)
1
: a piece of machinery
2
a
: the parts by which a machine operates
b
: the process, way, or system for achieving a goal
the mechanism of government
3
: the processes involved in or responsible for a natural occurrence (as evolution or an action or reaction)

Medical Definition

mechanism

noun
mech·​a·​nism ˈmek-ə-ˌniz-əm How to pronounce mechanism (audio)
1
: a piece of machinery
2
a
: 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
mechanistic adjective
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