#decameter__dekameter__decametre__dekametre__dam__dkm  a metric unit of length equal to ten meters
  supertype:  metric_linear_unit  a linear unit of distance in metric terms
  part of:  hectometer
  part:  meter__metre__m  the basic unit of length adopted under the System International d'Unites (approximately 1.094 yards)
     part:  decimeter__decimetre__dm  a metric unit of length equal to one tenth of a meter
        part:  centimeter__centimetre__cm  a metric unit of length equal to one hundredth of a meter
           part:  millimeter__millimetre__mm  a metric unit of length equal to one thousandth of a meter
              part:  micron__micrometer  a metric unit of length equal to one millionth of a meter
                 part:  nanometer__nanometre__millimicron__micromillimetre  a metric unit of length equal to one billionth of a meter
                    part:  angstrom_unit__angstrom__A  a metric unit of length equal to one ten billionth of a meter (or 0.0001 micron); used to specify wavelengths of electromagnetic radiation
                       part:  picometer__picometre__micromicron  a metric unit of length equal to one trillionth of a meter
                          part:  femtometer__femtometre__fermi  a metric unit of length equal to one quadrillionth of a meter

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