Which South American country is named after a line around the globe?

Answer

Its name is Spanish for 'equator', which crosses the country.

Context

Ecuador is the Spanish word for 'equator', and the country is named for the imaginary line of zero degrees latitude that passes through its territory just north of the capital, Quito. The name became official when the country left Gran Colombia in 1830 and was first called the State of Ecuador, after the earlier Spanish colonial district of Quito had been reorganized.

The line's fame owes a lot to the French Geodesic Mission, which arrived in the 1730s to measure a degree of latitude near the equator and compare it with measurements in Lapland. The results showed that Earth is slightly flattened at the poles and bulges at the equator. The mission gave the area worldwide scientific attention.

The tourist monument called Mitad del Mundo, 'Middle of the Earth', lies near Quito, but GPS measurements place the exact equator some distance away from it, a discrepancy often noted by visitors; a nearby museum marks the position found by modern instruments. Ecuador is not the only country on the equator, since several others, including Colombia, Brazil, Kenya and Indonesia, are crossed by it, but it is the only one named for it. The equator also gives the country's cities near it nearly equal day and night throughout the year.