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)

*{{quote-magazine, date=2013-08-10, volume=408, issue=8848, magazine=(The Economist)

, title= A new prescription , passage=As the world's drug habit shows, governments are failing in their quest to monitor every London window-box and Andean hillside for banned plants. But even that Sisyphean task looks easy next to the fight against synthetic drugs. No sooner has a drug been blacklisted than chemists adjust their recipe and start churning out a subtly different one.}}

Any set of instructions for preparing a mixture of ingredients.

By extension, a plan or procedure to obtain a given end result.

*{{quote-magazine, date=2014-06-21, volume=411, issue=8892, magazine=(The Economist)

, title= Magician’s brain , passage=[Isaac Newton] was obsessed with alchemy. He spent hours copying alchemical recipes and trying to replicate them in his laboratory. He believed that the Bible contained numerological codes. The truth is that Newton was very much a product of his time.}}

Now especially, a set of instructions for making or preparing food dishes.

A set of conditions and parameters of an industrial process to obtain a given result.