#fthm__fathom  a linear unit of measurement (equal to 6 feet) for water depth
  supertype:  linear_unit  a unit of measurement of length
  part:  yard__pace  a unit of length equal to 3 feet; defined as 91.44 centimeters; originally taken to be the average length of a stride
     part:  ft__foot  a linear unit of length equal to 12 inches or a third of a yard; "he is six feet tall"
        part:  inch__in  a unit of length (in United States and Britain) equal to one twelfth of a foot
           part:  ligne  a linear unit (1/40 inch) used to measure diameter of buttons
           part:  mesh  the number of opening per inch of a screen; measures size of particles; "a 100 mesh screen" or "100 mesh powdered cellulose"
           part:  mil  a unit of length equal to one thousandth of an inch; used to specify thickness (e.g., of sheets or wire)
           part:  pica_em__em__pica  a linear unit (1/6 inch) used in printing
              part:  point.linear_unit  a linear unit used to measure the size of type; approximately 1/72 inch
              part:  en__nut  half the width of an em

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