What is the term for a sudden overthrow of the government by a small group?

A coup d'état refers specifically to a sudden and often violent overthrow of an existing government, typically executed by a small group that could include military leaders, politicians, or other influential figures. This term indicates a swift and targeted action aimed at seizing power, usually without widespread public support or involvement, contrasting with terms that imply broader participation or societal change.

Revolution, on the other hand, generally denotes a more extensive and often popular movement aimed at changing the political system or society as a whole, involving mass mobilization and enduring shifts in power dynamics. Insurrection and uprising are also associated with rebellion against authority, but these terms imply resistance from a broader population or are often more focused on local conflicts rather than a quick takeover by a specific faction within the government or military.

Thus, the nuance of a coup d'état—grounded in the idea of a small, organized group acting decisively to unseat a government—makes it the correct term in this context.