Delegated legislation
From ACT Wiki
1. Law made by ministers under delegated powers given to them by Parliamentary Acts. Sometimes referred to as secondary legislation or subordinate legislation.
2.
A secondary source of UK tax law that is not written by parliament but usually by Her Majesty's Revenue & Customs.
3.
Law created by any other subordinate law-making body, within the authority of an Enabling Act - or other primary legislation - enacted by the primary law-making body.