From The Collaborative International Dictionary of English v.0.48:
Fiat \Fi"at\, n. [L., let it be done, 3d pers. sing., subj.
pres., fr. fieri, used as pass. of facere to make. Cf. Be.]
1. An authoritative command or order to do something; an
effectual decree.
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His fiat laid the corner stone. --Willis.
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2. (Eng. Law)
(a) A warrant of a judge for certain processes.
(b) An authority for certain proceedings given by the Lord
Chancellor's signature.
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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.
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