#psychrometer  a hygrometer consisting of a dry-bulb thermometer and a wet-bulb thermometer; their difference indicates the dryness of the surrounding air
  supertype:  hygrometer  measuring instrument for measuring the relative humidity of the atmosphere
  part:  dry-bulb_thermometer  an ordinary thermometer with a dry bulb; used to measure the air temperature
  part:  wet-bulb_thermometer  a thermometer with a bulb that is covered with moist muslin; used in a psychrometer to measure humidity

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