(1):
(pl.) of Apparatus
(2):
(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.
(3):
(n.) Things provided as means to some end.
(4):
(n.) A collection of organs all of which unite in a common function; as, the respiratory apparatus.