What is "decametre"

Decameter \Dec"a*me`ter\, Decametre \Dec"a*me`tre\, n. [F. d['e]cam[`e]tre; Gr. de`ka ten + m[`e]tre. See Meter.] A measure of length in the metric system; ten meters, equal to about 393.7 inches.

n. (SI-unit deca metre length)

n. a metric unit of length equal to ten meters [syn: decameter, dekameter, dekametre, dam, dkm]

A decametre or dekametre ( American spelling: dekameter, earlier decameter; symbol dam, sometimes unofficially Dm or dkm) is a very rarely used unit of length in the metric system, equal to ten metres.

This measure is included in the SI mostly for completeness: in principle, any combination of prefix and unit can be written, but many are rarely used in practice. One practical use of the decameter is for altitude of geopotential heights in meteorology. Meteorologists also use another seldom encountered SI prefix: hecto- in hectopascal (hPa). The volumetric form (see below) cubic decametre is convenient for describing large volumes of water such as in rivers and lakes.

The square decametre (dam) also known as the are (a), is the basis for the hectare (100 dam), the standard metric unit of land registry.