- Controlling device - One who, or that which, regulates. - A contrivance for regulating and controlling motion, as:
(a) The lever or index in a watch, which controls the effective length
of the hairspring, and thus regulates the vibrations of the balance.
(b) The governor of a steam engine. (c) A valve for controlling the
admission of steam to the steam chest, in a locomotive. - A clock, or other timepiece, used as a standard of
correct time. See Astronomical clock (a), under Clock. - A member of a volunteer committee which, in default of
the lawful authority, undertakes to preserve order and prevent crimes;
also, sometimes, one of a band organized for the comission of violent
crimes.