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.
In 2014 the man who once headed China's vast security apparatus was arrested, and two years later, Hu's top aide was jailed for life for corruption.
From BBC • Mar. 13, 2026
Dyszel built frames for neutron tracking detectors and assembled them within the experimental apparatus.
From Science Daily • Mar. 13, 2026
On a mission to modernise the army, he took over an apparatus facing stretched air defences, financial uncertainty, stalled peace talks, recruitment problems and widespread bureaucracy and war fatigue.
From Barron's • Mar. 12, 2026
But Iran’s state apparatus was built to outlive individual leaders, thanks to layered and overlapping centers of political and military power.
From The Wall Street Journal • Mar. 10, 2026
As soon as his head cleared and his stomach felt calmer, he sat up and called to the little spies.They were busy with some minute apparatus nearby.
From "The Amber Spyglass" by Philip Pullman
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.
