naut mi n 1: a British unit of length equivalent to 1,853.18 meters (6,082 feet) [syn: {nautical mile}, {mile}, {mi}, {geographical mile}, {Admiralty mile}] 2: a unit of length used in navigation; equivalent to the distance spanned by one minute of arc in latitude; 1,852 meters [syn: {nautical mile}, {mile}, {mi}, {knot}, {international nautical mile}, {air mile}]