E. Cobham Brewer 18101897. Dictionary of Phrase and Fable. 1898.
Coup dEtat (French)
means a state stroke, and the term is applied to one of those bold measures taken by Government to prevent a supposed or actual danger, as when a large body of men are arrested suddenly for fear they should overturn the Government.
The famous coup détat, by which Louis Napoleon became possessed of absolute
power, took place on December 2nd, 1851.