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
See More

Recent Examples on the Web

The case involves the executive branch’s attempt to force a private corporation to break the encryption and other security mechanisms on a product relied upon by the public to have private conversations. Cyrus Farivar, Ars Technica, "DOJ made secret arguments to break crypto, now ACLU wants to make them public," 28 Nov. 2018 The mayor also noted that if issues arise in the future about the contract, there is a new mechanism for review by the Police Department’s civilian inspector general. Steve Miletich, The Seattle Times, "Federal judge questions whether Seattle police-union contract in keeping with ‘spirit’ of reforms," 5 Nov. 2018 Name: Harlan Greenfield Patent: Wheelchair Accessible Forklift, a forklift with a flat platform that allows a person using a wheelchair to operate it and incorporates additional control mechanisms for disabled drivers. Popular Mechanics, "A Disabled Veteran Inspired Me To Invent the Forklift Anyone Can Drive," 29 Oct. 2018 However, footballers do have coping mechanisms behind the scenes to help them deal with those pressures, pranks being one of the main ones., "6 of the Biggest Pranksters in Football," 17 June 2018 Paddle a canoe Welcome to Disneyland's only attraction free of tracks, rails or other mechanisms designed to keep you on course. Scott Craven, USA TODAY, "5 under-the-radar things you've (probably) never done at Disneyland, but should," 25 May 2018 Some other jurisdictions use gas tax or other funding mechanisms. Scott Maxwell,, "15 questions for the candidates for Orange County mayor. Where do they stand?," 24 May 2018 Today, electric blowers and other mechanisms create a steady stream of air and maintain the appropriate pressure to control the organ’s sound. Elaine Schmidt, Milwaukee Journal Sentinel, "Lost in the rubble of Trinity church, a 'priceless and irreplaceable' pipe organ from 1879," 18 May 2018 The clinic provides real healing, tools and coping mechanisms to those suffering with complex mental illness, including addiction, bipolar disorder, schizophrenia, mood and personality disorders. Elizabeth Pudwill, Houston Chronicle, "Actor Sean Astin discusses mother Patty Duke's struggle with mental illness at Houston luncheon," 9 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.

See More

First Known Use of mechanism

1662, in the meaning defined at sense 1a

Keep scrolling for more

Learn More about mechanism

Statistics for mechanism

Last Updated

3 Dec 2018

Look-up Popularity

Time Traveler for mechanism

The first known use of mechanism was in 1662

See more words from the same year

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 \

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

Keep scrolling for more

More from Merriam-Webster on mechanism

Rhyming Dictionary: Words that rhyme with mechanism

Spanish Central: Translation of mechanism

Nglish: Translation of mechanism for Spanish Speakers

Britannica English: Translation of mechanism for Arabic Speakers Encyclopedia article about mechanism

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).


to enclose within walls

Get Word of the Day daily email!

Test Your Vocabulary

Late Autumn 2018 Words of the Day Quiz

  • frosted-autumn-leaves
  • Which is a synonym of yahoo?
Spell It

Can you spell these 10 commonly misspelled words?


Test Your Knowledge - and learn some interesting things along the way.


Love words? Need even more definitions?

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