Fiat /(?)/

Fi·at

Fiat

n.
  1. An authoritative command or order to do something; an effectual decree.
    His fiat laid the corner stone.
    — Willis.
  2. A warrant of a judge for certain processes. (Eng. Law)

Phrases & Compounds
Fiat money
irredeemable paper currency, not resting on a specie basis, but deriving its purchasing power from the declaratory fiat of the government issuing it.