ap·​pa·​ra·​tus | \ˌa-pə-ˈra-təs, -ˈrā- \
plural apparatuses or apparatus

Definition of apparatus 

1a : a set of materials or equipment designed for a particular use

b : a group of anatomical or cytological parts functioning together mitotic apparatus

c : an instrument or appliance designed for a specific operation an apparatus for measuring vision

2 : the functional processes by means of which a systematized activity is carried out the apparatus of society : such as

a : the machinery of government

b : the organization of a political party or an underground movement

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Examples of apparatus in a Sentence

Recent Examples on the Web

Smith and Sakib also studied the aerodynamics of knuckleballs with their apparatus and found that the flow will separate near the back of the ball any time the seam is located there mid-flight. Jennifer Ouellette, Ars Technica, "Physics can explain the fastball’s unexpected twist, new study finds," 23 Nov. 2018 Frank, who served time at 19, remembers how her experience as a white woman behind bars awakened her to the fact that a nation built on the ideals of fairness and justice had developed an unfair and unjust legal apparatus. Mattie Kahn, Glamour, "Inside a Radical Experiment to Transform the Lives of Incarcerated Women," 22 Aug. 2018 Lindbergh has fitted to his transatlantic plane is a econometer, an apparatus which holds a unit volume of gasoline., "April 29, 1927: Spirit of St. Louis takes flight," 29 Apr. 2018 Whelan is still gainfully employed by the conservative apparatus. David Roberts, Vox, "The caravan “invasion” and America’s epistemic crisis," 2 Nov. 2018 The resulting theory, quantum mechanics, deals with particles and blips of energy in the realm of the ultra-small, divorced from our everyday experience, and all but invisible to our clumsy mammalian sensory apparatuses. Tim Folger, Discover Magazine, "How Quantum Mechanics Lets Us See, Smell and Touch," 24 Oct. 2018 Volunteer and connect with your local party apparatus. Rachel Epstein, Marie Claire, "The Midterm Elections Can Be Confusing—Here's What You Need to Know About Them," 19 Sep. 2018 Shortly thereafter, Reza was identified by the regime’s domestic-security apparatus. Reza Pahlavi, WSJ, "Iranians Want Our Country Back," 15 Aug. 2018 Pressure will emerge from norm-centric circles to, ironically, ratify Trump’s misdeeds by refusing to even mount an attempt to clean house at the FBI, ICE, CBP, and other elements of the federal law enforcement apparatus. Matthew Yglesias, Vox, "Donald Trump, the resistance, and the limits of normcore politics," 3 July 2018

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

circa 1628, in the meaning defined at sense 1a

History and Etymology for apparatus

borrowed from Latin apparātus "act of preparing, display, trappings, equipment," from apparāre "to make ready, make preparations for" (from ad- ad- + parāre "to supply, provide, make ready") + -tus, suffix of verbal nouns — more at pare

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Statistics for apparatus

Last Updated

9 Dec 2018

Look-up Popularity

Time Traveler for apparatus

The first known use of apparatus was circa 1628

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More Definitions for apparatus



English Language Learners Definition of apparatus

: a tool or piece of equipment used for specific activities

: the organization or system used for doing or operating something


ap·​pa·​ra·​tus | \ˌa-pə-ˈra-təs, -ˈrā-\
plural apparatuses or apparatus

Kids Definition of apparatus

: the equipment or material for a particular use or job gymnasium apparatus laboratory apparatus


ap·​pa·​ra·​tus | \ˌap-ə-ˈrat-əs, -ˈrāt- \
plural apparatuses or apparatus

Medical Definition of apparatus 

: a group of anatomical and cytological parts having a common function the respiratory apparatus — see golgi apparatus

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Comments on apparatus

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


a knickknack or trinket

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