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

Hamas is rebuilding a new Gaza terror apparatus and using the ceasefire with Israel to boost its military, restore a problematic leadership structure and recruit a new generation of teenage fighters, according to a leading national security analyst. —Emma Bussey, FOXNews.com, 29 Dec. 2025

The numbers are modest, reflecting the limited size of Haiti’s security apparatus. —Jacqueline Charles, Miami Herald, 26 Dec. 2025

The wooden apparatus was replaced with a heavy-duty, metal trough. —Colleen Cronin, Boston Herald, 21 Dec. 2025

An immensely popular anti-colonial leader, Nyerere in 1965 created a single-party state governed by a robust and effective political party apparatus – first under the Tanganyika African National Union and later recast as Chama Cha Mapinduzi, or CCM. —Yonatan Morse, The Conversation, 19 Dec. 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