America
The United States of America, a large country of states.
America usually refers to the United States of America, a country of about 330 million people spread across fifty states, from Alaska in the far north to Hawaii in the Pacific Ocean. When someone says they're American or that they live in America, they almost always mean the United States.
This leads to some confusion. Technically, America can refer to two continents: North America (which includes Canada, the United States, Mexico, and Central American countries) and South America (which includes Brazil, Argentina, Chile, and other nations). People from any of these countries could call themselves American in this broader sense. However, in everyday English, when someone says America or American, they mean the United States and its citizens specifically.
The United States has played an enormous role in world history since its founding in 1776. From its system of representative democracy to its leadership in technology, entertainment, and innovation, American influence reaches across the globe. When you hear about American music, American movies, or American inventions, you're hearing about contributions from the United States specifically, though the country itself has always been shaped by people from all over the world who came seeking freedom and opportunity.