1. Abbr. mi. or mi A unit of length equal to 5,280 feet or 1,760 yards (1,609 meters), used in the United States and other English-speaking countries. Also called land mile, statute mile. See Table at measurement.
2. A nautical mile.
3. An air mile.
4. Sports A race that is one mile long.
5. A relatively great distance: had to walk for miles in the airport.
[Middle English, from Old English mīl, from Latin mīlia (passuum), a thousand (double paces), a Roman mile, pl. of mīlle, thousand; see gheslo- in the Appendix of Indo-European roots.]
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