plural apparatuses or apparatus
Definition of apparatus
1a : 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
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Time Traveler for apparatus
The first known use of apparatus was circa 1628
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