[1] : 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.
      1913 webster

            his fiat laid the corner stone.       --willis.
      1913 webster

   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.
          1913 webster

   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.
      1913 webster
see also:
be fiat money 

[2] : WordNet (r) 2.0

fiat
     n : a legally binding command or decision entered on the court
         record as if issued by a court or judge; "a friend in
         new mexico said that the order caused no trouble out
         there" syn: decree, edict, order, rescript
see also:
decree edict order rescript 

[3] : Moby Thesaurus II by Grady Ward, 1.0

40 moby thesaurus words for "fiat":
   appointment, authority, authorization, brevet, bull, certification,
   clearance, countenance, declaration, decree, decree-law,
   decreement, decretal, decretum, dictum, diktat, edict, edictum,
   empowerment, enabling, endorsement, enfranchisement, entitlement,
   ipse dixit, law, ordinance, ordonnance, proclamation,
   pronouncement, pronunciamento, ratification, rescript, rule,
   ruling, sanction, senatus consult, senatus consultum, ukase,
   warrant, warranty

[4] : Bouvier's Law Dictionary, Revised 6th Ed (1856)

fiat, practice. an order of a judge, or of an officer, whose authority, to 
be signified by his signature, is necessary to authenticate the particular 
acts. 

Fiat >> F Words
Fiat, definition of term: Fiat
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