Chile, officially the Republic of Chile, is a country in South America occupying a long and narrow coastal strip wedged between the Andes mountains and the Pacific Ocean. The Pacific forms the country's entire western border, with Peru to the north, Bolivia to the northeast, Argentina to the east, and the Drake Passage at the country's southernmost tip. Chile claims 1,250,000 km² of territory in Antarctica.

There are various theories about the origin of the word Chile. According to one theory the Incas of Peru, who had failed to conquer the Araucanians, called the valley of the Aconcagua "Chili" by corruption of the name of a tribal chief ("cacique") called Tili, who ruled the area at the time of the Incan conquest. Another theory points to the similarity of the valley of the Aconcagua with that of the Casma Valley in Peru, where there was a town and valley named Chili. Other theories say Chile may derive its name from the indigenous Mapuche word chilli, which may mean "where the land ends," "the deepest point of the Earth,", or "sea gulls;" or from the Quechua chin, "cold", or the Aymara tchili, meaning "snow." Another meaning attributed to chilli is the onomatopoeic cheele-cheele—the Mapuche imitation of a bird call.The Spanish conquistadors heard about this name from the Incas and the few survivors of Diego de Almagro's first Spanish expedition south from Peru in 1535-36 called themselves the "men of Chilli."

A long and narrow coastal Southern Cone country on the west side of the Andes Mountains, Chile stretches over 4,630 kilometers (2,880 mi) north to south, but only 430 kilometers (265 mi) at its widest point east to west. This encompasses a remarkable variety of landscapes.

At 756,950 km² (292,240 mi²), Chile is the world's 38th-largest country. It is comparable in size to Zambia, and is about twice the size of Japan.

The northern Atacama Desert contains great mineral wealth, primarily copper and nitrates. The relatively small Central Valley, which includes Santiago, dominates the country in terms of population and agricultural resources. This area also is the historical center from which Chile expanded in the late nineteenth century, when it integrated the northern and southern regions. Southern Chile is rich in forests, grazing lands, and features a string of volcanoes and lakes. The southern coast is a labyrinth of fjords, inlets, canals, twisting peninsulas, and islands. The Andes Mountains are located on the eastern border. Chile is the longest (N-S) country in the world (over 4,200 km / 2,600 mi), and also claims 1,250,000 square kilometers (482,628 sq. mi) of Antarctica as part of its territory. However, this latter claim is suspended under the terms of the Antarctic Treaty, of which Chile is signatory.

Chile controls Easter Island and Sala y Gómez Island, the easternmost islands of Polynesia, which it incorporated to its territory in 1888, and Robinson Crusoe Island, more than 600 kilometers (375 mi) from the mainland, in the Juan Fernández archipelago. Easter Island is nowadays a province of Chile. Also controlled but only temporally inhabited (by some local fishermen) are the small islands of Sala y Gómez, San Ambrosio and San Felix, these islands are notable because they extend Chile's claim to territorial waters out from its coast into the Pacific.