ap·​pa·​ra·​tus | \ ˌa-pə-ˈra-təs How to pronounce apparatus (audio) , -ˈrā- How to pronounce apparatus (audio) \
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

The Navy wanted professional-looking sailors who could wear firefighting masks and breathing apparatuses without interference. Jennifer Mcdermott, Fox News, "A hairy issue: Sailors tell the US Navy, 'We want beards'," 20 July 2018 Having mermaids who do not surface or rely on a visible breathing apparatus has been key to Weeki Wachee’s ethos since the beginning. Sarah Scoles, Washington Post, "These ‘mermaids’ dance underwater for half an hour at a time," 17 June 2018 Other equipment reaching its lifespan for replacement are the department's self-contained breathing apparatuses and cardiac monitors. Forrest Sellers,, "Montgomery to place 6-mill levy on May ballot," 17 Jan. 2018 Her role in creating a new financial regulatory apparatus gave her outsize influence over the bureaucracy. Kimberley A. Strassel, WSJ, "Biggest Loser: Elizabeth Warren," 8 Nov. 2018 Most CEOs have a huge and mostly invisible apparatus around them to prevent anything horrible from happening. Elizabeth Lopatto, The Verge, "After the SEC settlement, who will review Elon Musk’s tweets?," 5 Oct. 2018 The building will be designed to add 2 - 60 foot deep apparatus bays in the future. Dana Burke, Houston Chronicle, "Pearland to break ground on new fire station Thursday," 12 June 2018 In theory, Trump sits atop the most expansive intelligence-gathering apparatus in history. Matt Ford, The New Republic, "The World’s Most Powerful Rube," 4 June 2018 The basement walls and apparatus bay footers have been poured and the first floor walls will be begin taking shape soon. Julie A. Short/special To,, "North Ridgeville Visitors Bureau hosts annual 'Discover the Ridge': Short Takes on Avon, Avon Lake and North Ridgeville," 29 Apr. 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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Last Updated

18 Mar 2019

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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 How to pronounce apparatus (audio) , -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 How to pronounce apparatus (audio) , -ˈrāt- How to pronounce apparatus (audio) \
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).


to corrupt or become corrupted

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