fiat
UK[ˈfiːæt]US[ˈfiː.ɑːt]
n
An official order or authorization given by a person in authority.
n
An arbitrary decree or command.
Etymology
The word 'fiat' entered English in the early 17th century directly from Latin, where it is the third-person singular present subjunctive of the verb 'fieri', meaning 'let it be done'. This form was used in the Latin Vulgate Bible's account of creation, "fiat lux" ("let there be light"), imbuing the term with a sense of authoritative command by divine or sovereign will. The semantic journey traces from this specific, powerful phrase of creation to a general term for any authoritative sanction or decree issued by a government or leader. Its modern abstract meaning retains the core logic of a pronouncement that brings something into effect purely by the authority behind it, not through consensus or inherent reason.
Analysis
This word is a direct loanword from Latin and is not productively segmented using English spelling morphemes. It functions as a simplex noun.
Examples
The project can only proceed by fiat of the board of directors.
He ruled the company by fiat, rarely consulting his managers.
The government's fiat imposed new regulations on the industry.