fiat has definitions from the fields of law,writing
1
[ noun ] (law,writing) a legally binding command or decision entered on the court record (as if issued by a court or judge)

Examples

"a friend in New Mexico said that the order caused no trouble out there"

Used in print

(The Rev. John A. O'Brien, "Let's Take Birth Control...)

To try to oppose the general religious and moral conviction of such a majority by a legislative fiat would be to invite the same breakdown of law and order that was occasioned by the ill-starred Prohibition experiment .

(Randall Stewart, "A Little History, a Little Honesty: A...)

I was having lunch not_long ago ( apologies to N._V._Peale ) with three distinguished historians ( one specializing in the European Middle_Ages , one in American history , and one in the Far_East ) , and I asked them if they could name instances where the general mores had been radically changed with `` deliberate speed , majestic instancy '' ( Francis_Thompson 's words for the Hound_of_Heaven 's pursuit ) by judicial fiat .

(Morton A. Kaplan and Nicholas de B. Katzenbach,...)

The European customs on which international_law was based were to become , by force and fiat , the customs that others were to accept as law if they were to join this community as sovereign states .

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