relative humidity
noun
the amount of water vapor in the air, expressed as a percentage of the maximum amount that the air could hold at the given temperature; the ratio of the actual water vapor pressure to the saturation vapor pressure. Abbreviation: RH, rh
Also called
humidity.
Origin of relative humidity
First recorded in 1810–20
Words nearby relative humidity
British Dictionary definitions for relative humidity
relative humidity
noun
the mass of water vapour present in the air expressed as a percentage of the mass that would be present in an equal volume of saturated air at the same temperature
Compare absolute humidity
Medical definitions for relative humidity
relative humidity
n.
The ratio of the amount of water vapor in the air at a specific temperature to the maximum amount that the air could hold at that temperature, expressed as a percentage.
Scientific definitions for relative humidity
relative humidity
The ratio of the actual amount of water vapor present in a volume of air at a given temperature to the maximum amount that the air could hold at that temperature, expressed as a percentage. Warm air can hold more water vapor than cool air, so a particular amount of water vapor will yield a lower relative humidity in warm air than it does in cool air. Compare absolute humidity.