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

• equipment
• gear

Examples of apparatus in a Sentence

Recent Examples on the Web

The Hall of Flame Museum of Firefighting in Phoenix, home to the world’s largest collection of fire apparatus, is seeking the community’s help after recent flood damage. —Wren Smetana, AZCentral.com, 25 Oct. 2025

Once set, five-year plans act as marching orders for officials across the sprawling apparatus of the government and a guide for businesses, universities and other organizations on how to align their own strategies with the party’s. —Simone McCarthy, CNN Money, 24 Oct. 2025

In some ways, IndyCar is more independent, where the individual holds more of an onus to deliver versus the entire apparatus. —Nick Remsen, Vogue, 24 Oct. 2025

The apparatus is an automatic closed system that incorporates a fermentation vat and a centrifuge to simulate lunar gravity. —David Szondy october 19, New Atlas, 19 Oct. 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