if a unit for something is being measured, then it requires a measurement tool for measuring that something
metric_unit_of_measure is unit_of_measure. mental_measurement is measurement. gauge is measuring_instrument. us_unit_of_measure is unit_of_measure. gauge is measuring_device. reading is measurement. measuring_unit is unit_of_measurement. meter is measuring_instrument. metric_unit is unit_of_measurement. system_of_measurement is measure.