The term "national sovereignty" refers to the authority of a nation-state to govern itself without external interference. It embodies the principles of self-determination and independence, allowing a state to make decisions regarding its laws, policies, and governance without external influence. National sovereignty is crucial for maintaining territorial integrity and political autonomy, and it often comes into play during international relations and conflicts. It can also be challenged by global agreements, international law, or supranational entities that may impose regulations affecting state actions.