apparatus
Americannoun
plural
apparatus, apparatuses-
a group or combination of instruments, machinery, tools, materials, etc., having a particular function or intended for a specific use.
Our town has excellent fire-fighting apparatus.
-
any complex instrument or mechanism for a particular purpose.
- Synonyms:
- contrivance, contraption, device, appliance, machine
-
any system or systematic organization of activities, functions, processes, etc., directed toward a specific goal.
the apparatus of government; espionage apparatus.
-
Physiology. a group of structurally different organs working together in the performance of a particular function.
the digestive apparatus.
noun
-
a collection of instruments, machines, tools, parts, or other equipment used for a particular purpose
-
a machine having a specific function
breathing apparatus
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the means by which something operates; organization
the apparatus of government
-
anatomy any group of organs having a specific function
Usage
Plural word for apparatus The plural form of apparatus can be either apparatus or apparatuses. The appropriate plural form depends on whether the term is considered to be a mass (uncountable) noun (like air or rice) or a count noun (like apple or car). When used as a mass noun, the correct plural form is apparatus, as in The lab apparatus must be removed before the lab can be painted. When used as a count noun, the correct plural form is apparatuses, as in The ship is equipped with apparatuses for security, cargo loading, and more. The plurals of several other singular words that end in -s are also formed the same way, such as pass/passes, lotus/lotuses, and dress/dresses. In some nouns that end in -us that are derived from Latin, the irregular plural ending -i may be used instead, as in fungus/fungi or cactus/cacti. These nouns are considered irregular nouns.However, this ending is not valid for apparatus. Apparati would be an invalid plural for apparatus.
Etymology
Origin of apparatus
1620–30; < Latin apparātus equipment, originally the act of equipping, preparation, equivalent to apparā ( re ) to prepare ( ap- ap- 1 + parāre; prepare ) + -tus suffix of v. action
Example Sentences
Examples are provided to illustrate real-world usage of words in context. Any opinions expressed do not reflect the views of Dictionary.com.
Its media apparatus has become the main source of information for people living in the country, particularly when the internet is cut off.
From BBC • Mar. 15, 2026
From Washington and Ottawa to Europe and Japan, money is flowing into the apparatus of war and security on levels not seen in decades.
From The Wall Street Journal • Mar. 13, 2026
Dyszel built frames for neutron tracking detectors and assembled them within the experimental apparatus.
From Science Daily • Mar. 13, 2026
It is an apparatus that has been integrated into this administration at the structural level.
From Salon • Mar. 9, 2026
What took up the slack was the shrewdness and craft of Rutherford’s associates, their ability to extract the maximum results from experimental apparatus of marked simplicity and elegance.
From "Big Science" by Michael Hiltzik
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Definitions and idiom definitions from Dictionary.com Unabridged, based on the Random House Unabridged Dictionary, © Random House, Inc. 2023
Idioms from The American Heritage® Idioms Dictionary copyright © 2002, 2001, 1995 by Houghton Mifflin Harcourt Publishing Company. Published by Houghton Mifflin Harcourt Publishing Company.