from
The Collaborative International Dictionary of English v.0.48
Apparatus \Ap"pa*ratus\, n.; pl. {Apparatus}, also rarely
{Apparatuses}. [L., from apparare, apparatum, to prepare; ad
+ prepare to make ready.]
1. Things provided as means to some end.
[1913 Webster]
2. 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.
[1913 Webster]
3. (Physiol.) A collection of organs all of which unite in a
common function; as, the respiratory apparatus.
[1913 Webster]