Ap"pa*ratus (#), n.; pl. Apparatus, also rarely Apparatuses (#). [L., from apparare, apparatum, to prepare; ad + prepare to make ready.]
Things provided as means to some end.
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.
A collection of organs all of which unite in a common function; as, the respiratory apparatus.
© Webster 1913.