1. A British unit of length equivalent to 1,853.18 meters (6,082 feet); SYN. naut mi, mile, mi, geographical mile, Admiralty mile.
2. A unit of length used in navigation; equivalent to the distance spanned by one second of arc in latitude; 1,852 meters; SYN. mile, mi, naut mi, knot, international nautical mile, air mile.
Formerly various units of distance used in navigation; since 1959, an internationally agreed-on standard equaling the average length of one minute of arc on a great circle of the Earth, or 6,076.12 ft/1,852 m.