kilometer

A kilometer, symbol: km is a unit of length in the metric system equal to 1000 meters (from the Greek words χίλια (khilia) = thousand and μέτρο (metro) = count/measure). It is approximately equal to 0.621 miles, 1094 yards or 3281 feet.

Slang terms for kilometer include "klick" (sometimes spelt "click" or "klik") and "kay" (or "k"). All these slang terms can also refer to kilometers per hour.

Metric system

Main articles: Metric system and Meter

Like the kilometer, all units of length in the metric system are based on the meter, by adding an SI prefix that stands for a power of ten, such as hecto for one hundred to form hectometer (= 0.1 kilometer) or mega for one million to form megameter (= 1,000 kilometer).

The meter is not only the basis for all units of length in the metric system, but also of units of area (the square meter) and volume (the cubic meter). This extends to the kilometer, so one can have square and cubic kilometers.

Unicode has symbols for "km" (㎞), for square kilometer (㎢) and for cubic kilometer (㎦); however, they are useful only in CJK texts, where they are equal in size to one Chinese character.

See also

hectometer << kilometer << megameter

• Orders of magnitude, 1 E3 m
• SI, SI prefix
• mile, verst