1. a unit of measurement of length in the imperial system, equal to 5280 feet (1609.34 m).
2. nautical, international nautical or sea mile, a unit of measurement of length used in marine or aeronautical navigation, equal to 1852 m. The Admiralty nautical mile, used until recently, is 6080 feet (approx 1853.2 m).
3. any of various other lengths ascribed to the mile in different periods and in different countries.
4. ( often plural ) a large distance or quantity.
[ME myle, OE mil, from L milia ( passuum ) a thousand (paces)]