I guess it is
coup d'é⋅tat–noun, plural coups d'é⋅tat
|a sudden and decisive action in politics, esp. one resulting in a change of government illegally or by force.|
1640–50; < class="luna-Img" src="http://cache.lexico.com/dictionary/graphics/luna/thinsp.png" alt="" border="0">
overthrow, rebellion, revolution, uprising.