Kilometer (noun)

A metric unit of length equal to 1000 meters (approximately 0.621371 miles).

Origin:

Early 19th century: from french kilomètre, from greek khilioi "thousand" + french mètre "metre".

Examples:

1. He ran 10 kilometers.
2. She drove 100 kilometers.
3. The race was 42.195 kilometers long.
4. The distance was measured in kilometers.
5. The speed limit was 80 kilometers per hour.