Apparatus

n. device; system

An apparatus (plural apparatus, apparatuses) may be one of the following:A machine.A fire engine or fire truck.Reference tools added to a book, apart from the text, such as variant readings or translations, textual notes, a concordance, a bibliography or an index, designed for the use of scholars studying the book.One or more pieces of equipment on or with which gymnastics is performed.The State apparatus, the formal and material means (including the repressive state apparatus: legal system, the police, armed forces, etc.) by which the ruling class exercises power: a term used by some Marxist theorists including Louis Althusser (see Ideological State Apparatuses).Apparatus theory, derived in part from Marxist film theory, semiotics, and psychoanalysis, was a dominant theory within cinema studies during the 1970s.Golgi apparatus (also called a Golgi body, Golgi complex, or dictyosome) is an organelle found in most eukaryotic cells.The Red Jumpsuit Apparatus, a post-hardcore band.
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Noun
1. equipment designed to serve a specific function
(synonym) setup
(hypernym) equipment
(hyponym) aerator
2. (anatomy) a group of body parts that work together to perform a given function; "the breathing apparatus"
(hypernym) body part
(hyponym) auditory apparatus
(classification) anatomy, general anatomy

(pl. )
of Apparatus
  

(n.)
Things provided as means to some end.
  

(n.)
Hence: A full collection or set of implements, or utensils, for a given duty, experimental or operative; any complex instrument or appliance, mechanical or chemical, for a specific action or operation; machinery; mechanism.
  

(n.)
A collection of organs all of which unite in a common function; as, the respiratory apparatus.
  

noun
equipment used in a laboratory or hospital; the hospital has installed new apparatus in the physiotherapy department; the blood sample was tested in a special piece of apparatus
NOTE: no plural: a piece of apparatus; some new apparatus