dew point

noun
1.
the temperature to which air must be cooled, at a given pressure and water-vapor content, for it to reach saturation; the temperature at which dew begins to form.
Also called dew-point temperature.
Compare absolute humidity, mixing ratio, relative humidity, specific humidity.
Origin
1825-35
Examples from the web for dew point
  • The temperature was near the dew point and steam was rising off its body.
  • dew point temperature is a measure of atmospheric moisture.
  • The dew point is the temperature at which a vapor begins to condense at a constant pressure.
  • dew point will be determined by one of the two procedures included in this test method.
  • Tables are available for determining the dew point given the vapor pressure.
British Dictionary definitions for dew point

dew point

noun
1.
the temperature at which water vapour in the air becomes saturated and water droplets begin to form
dew point in Science
dew point  
The temperature at which the water vapor contained in a volume of air at a given atmospheric pressure reaches saturation and condenses to form dew. The dew point varies depending on how much water vapor the air contains, with humid air having a higher dew point than dry air. When large droplets of condensation form, they are deposited onto surfaces as dew. When smaller droplets form, they remain suspended in the air as mist or fog. If the dew point is below the freezing temperature of water (0°C), the water vapor turns directly into frost by sublimation.