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

The apparatus converts mechanical inputs of the propeller and airframe systems to electronic signals, which can be measured by the electronic control. Kris Osborn, Fox News, "Massive overhaul to keep Air Force C-130 flying for 80 years into 2030s," 25 June 2018 Importantly, this kind of shield was not part of Eagleworks’ original testing apparatus either, which suggests the original findings could also be a consequence of leaking magnetic fields. National Geographic, "NASA's 'Impossible' Space Engine Tested—Here Are the Results," 22 May 2018 And, as to potential mechanical collapses, the giant pipe is broken up by bulkheads, to prevent one flooded section from dragging down the whole apparatus. James Rainey /, NBC News, "A young Dutch inventor wants to clean plastic from the ocean. Can he do it?," 13 June 2018 Some Democrats accused Obama of neglecting the Democratic Party apparatus while in the White House, but people close to the former president argue he is fully invested in the future of the party and the bench of talent looking to run on 2020. Dan Merica, CNN, "Obama meeting with 2020 hopefuls to discuss party future, running in the age of Trump," 11 June 2018 The best part of the toilet, or the least-terrible part of it, is the peeing apparatus. Author: Avi Selk, Anchorage Daily News, "NASA astronaut reveals the lows of space travel: packing poop with her hand," 30 May 2018 The best part of the toilet, or the least-terrible part of it, is the peeing apparatus. The Washington Post,, "The worst thing in all of space travel may be pooping," 29 May 2018 The team concluded that the force was produced by Earth’s magnetic field leaking into the apparatus rather than any exotic new physics. David Hambling, Popular Mechanics, "New Study Casts Doubt on the "Impossible" EmDrive," 24 May 2018 That's because Apple has designed the MacBook Pro such that fixing even one key requires replacing the entire keyboard apparatus, as well as part of the metal enclosure and some other components. Samuel Axon, Ars Technica, "Report: Butterfly MacBook Pro keyboards require more frequent, more expensive repairs," 8 May 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

14 Oct 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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