A decametre (International spelling as used by the International Bureau of Weights and Measures,[1][2] American spelling dekameter or decameter,[3][4]), symbol dam ("da" for the SI prefix deca-,[1] "m" for the SI unit metre), is a unit of length in the International (metric) System of Units equal to ten metres.

Unit systemmetric
Unit oflength
1 dam in ...... is equal to ...
   SI units   10 m
   imperial/US units   10.936 yd
 393.70 in

While any combination of SI prefix and unit can be used, many are rarely used in practice; the decametre is used less frequently than other units of length. One practical use is for altitude of geopotential heights in meteorology. The volumetric form cubic decametre is convenient for describing large volumes of water such as in rivers and lakes[citation needed]; a volume of one cubic decametre (dam3) is equivalent to a capacity of one megalitre (ML).

One technical atmosphere is the pressure of one decameter of water. Also, the are (a), a metric unit for land area, is equal to one square decametre (dam2).

See alsoEdit


  1. ^ a b "Decimal multiples and submultiples of SI units" (8th ed.). SI Brochure: The International System of Units (SI). 2006.
  2. ^ "Unit of length (metre)". SI Brochure: The International System of Units (SI) (8th ed.). 2006.
  3. ^ "The Two Classes of SI Units and the SI Prefixes". The NIST Guide for the Use of the International System of Units. 2008.
  4. ^ "Decametre definition and meaning". Collins Dictionary. Retrieved 27 July 2020.