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 of apparatus

• equipment
• gear

Examples of apparatus in a Sentence

Recent Examples on the Web

As a nuclear power, Pakistan commands a sophisticated defense apparatus comprising an army, navy, air force, and marine corps. —Sophia Saifi, CNN Money, 27 Feb. 2026

Amnesty International Brazil said the case revealed police corruption, obstruction of justice and the operation of organized crime within the state apparatus. —Arkansas Online, 26 Feb. 2026

Potentially lethal high voltages, dangerous ultraviolet and X-ray radiation and a high-vacuum apparatus that can implode if improperly handled. —Miriam Fauzia, Dallas Morning News, 26 Feb. 2026

Telecommunications and surveillance Celia Margarita Reyes Ochoa, deputy director general of TELCOR since 2023, was designated for her role in the telecommunications regulator, which Washington describes as a pillar of the government’s surveillance apparatus. —Antonio María Delgado, Miami Herald, 26 Feb. 2026

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