Kilometre
The kilometre is the common unit of longer distances on Earth. The SI unit is the metre, the kilometre is 1000 metres. It is now used more than the statute mile for road distances, and the nautical mile for sea distances and air distances. Also, kilometres per hour replaces knots and miles per hour, e.g. on an odometer.
It is also spelled kilometer. This spelling is used in American English.
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