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
-
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; see prepare) + -tus suffix of v. action
Explanation
Your apparatus is the collective equipment you use for specific purposes. For example, the apparatus used for scuba diving includes goggles, flippers, and a breathing tank, while a surgeon’s apparatus includes various scalpels and clamps. Different activities, different apparatuses. The noun apparatus evolved from the Latin apparātus, meaning "equipment or preparation." It might refer to one item, (a breathing apparatus) or a group of items (sports apparatus). Here’s a spelling tip: often, when a word ends in -us, the plural ending changes to i — “alumnus/alumni,” “focus/foci.” However, apparatus is part of the group that doesn't change — words like “virus/viruses” or “census/censuses.” This means the plural is either apparatus or apparatuses, though the latter is more common.
Vocabulary lists containing apparatus
Orbiting Jupiter
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Among the Hidden
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The Time Machine
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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.
Apparatus engineers at Cal Fire are responsible for operating and maintaining fire engines and water tanks during emergency responses.
From BBC • Sep. 20, 2024
Under a deal brokered by city elders, the SDF late on Tuesday handed Hamza over to a third faction, the Stabilisation Support Apparatus.
From Reuters • Aug. 16, 2023
Carey didn’t have to wait for the Olympic trials to secure her spot in Tokyo as she clinched her spot as an individual through the Apparatus World Cup Series in April 2020.
From Los Angeles Times • Jul. 28, 2021
At one point, he ran a mop factory; at another, he hawked something called an Electro-Therapeutic Apparatus, which provided its owners with the putative health benefits of mild, recurrent electrocution.
From The New Yorker • Apr. 24, 2019
I requested Octav. to bespeak an Apparatus from a Glazier but he would not & defied me.
From "The Astonishing Life of Octavian Nothing, Traitor to the Nation, Volume II: The Kingdom on the Waves" by M.T. Anderson
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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.