Hydraulics

Also used to collectively refer to a set of systems which utilize hydraulic principles to function. The most common examples are control systems inside vehicles (typically aircraft) where such systems are used to move control surfaces such as elevators and ailerons. Example: "We did a thorough check of the hydraulics last week; everything's fine."

Hy*drau"lics (?), n. [Cf. F. hydraulique.]

That branch of science, or of engineering, which treats of fluids in motion, especially of water, its action in rivers and canals, the works and machinery for conducting or raising it, its use as a prime mover, and the like.

⇒ As a science, hydraulics includes hydrodynamics, or the principles of mechanics applicable to the motion of water; as a branch of engineering, it consists in the practical application of the mechanics of fluids to the control and management of water with reference to the wants of man, including canals, waterworks, hydraulic machines, pumps, water wheels, etc. Some writers treat hydraulics and hydrostatics as subdivisions of hydrodynamics.

© Webster 1913.