What is the legal or formal name for a mile?

The legal or formal name for a mile is defined as 5280 feet. This measurement is universally accepted and standardized in the United States customary system. The mile is a unit of length used primarily in the United States and a few other countries. The specific length of 5280 feet derives from historical definitions and has been standardized for use in various applications, including aviation, where precise distance measurements are crucial for navigation and safety.

The other options may sound plausible in different contexts but do not define a mile. For instance, a nautical mile, used primarily in maritime and aerial navigation, is based on the circumference of the Earth and is equal to approximately 6076.12 feet. A statute kilometer is a metric unit that is equal to 1000 meters, which is not relevant to the definition of a mile. Additionally, five thousand feet is not a legally recognized measure for a mile, as it falls short of the actual 5280 feet measurement.