WordNet (r) 3.0 (2006):

naut mi
    n 1: a former British unit of length equivalent to 6,080 feet
         (1,853.184 meters); 800 feet longer than a statute mile
         [syn: nautical mile, naut mi, mile, mi,
         geographical mile, Admiralty mile]
    2: a unit of length used in navigation; exactly 1,852 meters;
       historically based on the distance spanned by one minute of
       arc in latitude [syn: nautical mile, mile, mi, naut
       mi, knot, international nautical mile, air mile]