From the Latin noun nauta, meaning "sailor, mariner," we get the word nautical, meaning anything "related to, or associated with sailors, navigation, or ships." A nautical mile was historically defined as "the meridian arc length corresponding to one minute (1/60 of a degree) of latitude," as nautical miles were used for sailing, and sailing required adjustments for the curvature of the earth. Today, an international nautical mile is defined as exactly 1,852 meters, or 6,076 feet, which is actually 1.151 miles. By the way, one nautical mile per hour is called a knot, and the homophonic unit of measurement is used by ships and aircraft—essentially any craft that must account for the curvature of the earth when traveling long distances.