apparatus

noun

ap·​pa·​ra·​tus ˌa-pə-ˈra-təs  -ˈrā- 

plural apparatuses or apparatus

1

a

: 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

Synonyms

• accoutrements
• accouterments
• equipment
• gear
• hardware
• kit [chiefly British]
• material(s)
• matériel
• materiel
• outfit
• paraphernalia
• stuff
• tackle

Examples of apparatus in a Sentence

Recent Examples on the Web

His grip on the country’s military and intelligence apparatus has grown. —Antonio Maria Delgado, Miami Herald, 3 June 2025

The retirement apparatus, layered over decades of tech and regulation, is textbook complex. —Miguel Kudry, Forbes.com, 28 May 2025

Listen to this article With cancer the number one cause of death for firefighters, Connecticut lawmakers are considering a bill that would allocate $3 million to replace fire apparatus thought to be causing cancer. —Livi Stanford, Hartford Courant, 20 May 2025

Fire department employee rolls show that Robinson is a fire apparatus operator with a 2025 salary of $104,332. —Judy L. Thomas, Kansas City Star, 19 May 2025

Word History

Etymology

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

First Known Use

circa 1628, in the meaning defined at sense 1a

Phrases Containing apparatus

• Golgi apparatus

Rhymes for apparatus

• superlattice
• beatus
• flatus
• gratis
• lattice
• rattus
• satis
• status
• stratus

Kids Definition

apparatus

noun

ap·​pa·​ra·​tus ˌap-ə-ˈrat-əs  -ˈrāt- 

plural apparatuses or apparatus

1

: the equipment or material for a particular use or job

laboratory apparatus

2

: a complicated instrument or device

Medical Definition

apparatus

noun

ap·​pa·​ra·​tus ˌap-ə-ˈrat-əs  -ˈrāt- 

plural apparatuses or apparatus

: a group of anatomical and cytological parts having a common function

the respiratory apparatus

see golgi apparatus