fiat

noun

fi·​at ˈfē-ət 

-ˌat,

-ˌät;

ˈfī-ət,

-ˌat 

1

: an authoritative or arbitrary order : decree

government by fiat

2

: an authoritative determination : dictate

a fiat of conscience

3

: a command or act of will that creates something without or as if without further effort

According to the Bible, the world was created by fiat.

Synonyms

• decree
• edict
• ruling
• directive

Examples of fiat in a Sentence

He runs the company by fiat.

the school principal issued a fiat that caps were not to be worn inside the school, and that was that

Recent Examples on the Web

However, users need to be able to convert these digital assets to fiat currency and back again. —Kate Drew, Forbes.com, 19 June 2025

And unlike sovereign bonds or fiat currencies, gold carries no counterparty risks, Melek said. —Lee Ying Shan, CNBC, 17 June 2025

The novel resolves as if by fiat: Alison turns in her book, watches some birds, picks some flowers; Naomi moves in with Stuart and Sparrow (and Lois and Ginger) without any great upheaval. —Andrea Long Chu, Vulture, 16 June 2025

Anthony Napolitano, 41st, and approved by the Committee on License and Consumer Protection that would give aldermen the power to outright ban Airbnbs by aldermanic fiat and then force Airbnb and its competitors to collect signatures to overturn the ban and stay in business. —The Editorial Board, Chicago Tribune, 13 June 2025

Word History

Etymology

Latin, let it be done, 3rd singular present subjunctive of fieri to become, be done — more at be

First Known Use

circa 1631, in the meaning defined at sense 3

Phrases Containing fiat

• fiat money

Kids Definition

fiat

noun

fi·​at ˈfē-ət  -at 

-ät;

ˈfī-ət,

-at

: an order from someone in charge

Legal Definition

fiat

noun

fi·​at ˈfē-ˌät, -ˌat, -ət; ˈfī-ˌat 

1

: decree

2

: an authoritative but arbitrary order

a brazen act of judicial fiat

—L. H. Tribe