noun ap·pa·ra·tus \ˌa-pə-ˈra-təs, -ˈrā-\

: a tool or piece of equipment used for specific activities

: the organization or system used for doing or operating something

plural ap·pa·ra·tus·es or ap·pa·ra·tus

Full Definition of APPARATUS

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
:  the functional processes by means of which a systematized activity is carried out <the apparatus of society>: as
a :  the machinery of government
b :  the organization of a political party or an underground movement

Examples of APPARATUS

  1. She fell off a gymnastics apparatus and broke her leg.
  2. <the hospital's operating rooms boast the very latest medical apparatus>


Latin, from apparare to prepare, from ad- + parare to prepare — more at pare
First Known Use: circa 1628

Other Anatomy Terms

bilateral symmetry, carotid, cartilage, dorsal, entrails, prehensile, renal, solar plexus, supine, thoracic, ventral

Rhymes with APPARATUS

APPARATUSES Defined for Kids


noun ap·pa·ra·tus \ˌa-pə-ˈra-təs, -ˈrā-\
plural ap·pa·ra·tus·es or apparatus

Definition of APPARATUS for Kids

:  the equipment or material for a particular use or job <gymnasium apparatus> <laboratory apparatus>
Medical Dictionary


noun ap·pa·ra·tus \ˌap-ə-ˈrat-əs, -ˈrāt-\
plural ap·pa·ra·tus·es or ap·pa·ra·tus

Medical Definition of APPARATUS

:  a group of anatomical and cytological parts having a common function <the respiratory apparatus>—see golgi apparatus


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