n.
Pronunciation: ' f ē - ə t, - ˌ at, - ˌ ät; ' f ī - ə t, - ˌ at
Function: noun
Etymology: Latin, let it be done, 3d singular present subjunctive of fieri to become, be done ― more at BE
Date: circa 1631
1 : a command or act of will that creates something without or as if without further effort
2 : an authoritative determination : DICTATE <a fiat of conscience>
3 : an authoritative or arbitrary order : DECREE <government by fiat >