The word state has several meanings:

1. A region with its own government within a larger country. The United States has fifty states, each with its own capital, laws, and legislature. California, Texas, and New York are states. Other countries have similar divisions: Germany has states called Länder, and Australia has states like Queensland and Victoria.
2. A country itself, especially when discussing government or politics. When diplomats talk about relations between states, they mean relations between nations. The head of state is the official leader of a country.
3. The condition something is in at a particular time. Water can exist in three states: solid (ice), liquid (water), and gas (steam). You might describe your room's state after forgetting to clean it all week, or check the state of your homework before turning it in. When doctors monitor a patient's state, they're tracking how well or poorly the person is doing.
4. To say something clearly and formally. When you state your opinion, you express it directly. A witness in court must state the facts. A written statement is an official declaration of information or position.

The phrase state of mind describes someone's emotional or mental condition at a particular moment.