#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
  supertype:  metric_linear_unit  a linear unit of distance in metric terms
  part of:  nanometer
  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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