Separation of Powers: The division of governmental responsibilities among different branches to prevent concentration of power. (Example: The U.S. Constitution separates powers into three branches: legislative, executive, and judicial.)
Impeachment: A process by which an official can be removed from office for serious wrongdoing. It is usually initiated by the legislative branch. (Example: Congress has the power to impeach and remove presidents.)
Veto: The power held by the President to reject bills passed by Congress, preventing them from becoming laws unless overridden by a two-thirds majority vote in both houses.