A unit of length used in marine navigation that is equal to a minute of arc of a great circle on a sphere. One international nautical mile is equivalent to 1,852 meters or 1.151 statue miles. Please not that this is different to a UK Nautical mile.
A unit of distance equal to 3.0 statute miles (4.8 kilometers). Note that there also Nautical Leagues, UK Leagues and UK Nautical Leagues which all differ.