Noun

(uncountable)   The act of regulating or the condition of being regulated.

(countable)   A law or administrative rule, issued by an organization, used to guide or prescribe the conduct of members of that organization.

*{{quote-magazine, date=2013-05-17

, author=George Monbiot, authorlink=George Monbiot , title=Money just makes the rich suffer , volume=188, issue=23, page=19 , magazine=(The Guardian Weekly) citation , passage=In order to grant the rich these pleasures, the social contract is reconfigured. […]  The public realm is privatised, the regulations restraining the ultra-wealthy and the companies they control are abandoned, and Edwardian levels of inequality are almost fetishised.}}

* Army regulations state a soldier AWOL over 30 days is a deserter.

(European Union law) A form of legislative act which is self-effecting, and requires no further intervention by the Member States to become law.

(lb) Mechanism controlling DNA transcription.

(lb) Physiological process which consists in maintaining homoeostasis.

Noun

(en noun)

One who controls something.

* (rfdate) (Dryden)

The great controller of our fate / Deigned to be man, and lived in low estate.

(business) A person who audits, and manages the financial affairs of a company or government; a comptroller.

(computing) A mechanism that controls or regulates the operation of a machine, especially a peripheral device in a computer.

(nautical) An iron block, usually bolted to a ship's deck, for controlling the running out of a chain cable. The links of the cable tend to drop into hollows in the block, and thus hold fast until disengaged.