Mile_1

Mile, Nautical, the length of a minute of the meridian. It varies, therefore, according to the latitude. It is, in other words, equal to a minute of arc on a circle whose radius is the radius of the curvature of the meridian at the latitude of the place. [Degree.] It is important to distinguish this from the geographical mile, which is the length of a minute of arc on the earth's equator, and is therefore a constant quantity - viz. 6,080 feet, and equals the Admiralty knot or mile (1-151 statute mile).