relative humidity

noun

: the ratio of the amount of water vapor actually present in the air to the greatest amount possible at the same temperature

Examples of relative humidity in a Sentence

Recent Examples on the Web
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In those counties, relative humidity is forecast to dip as low as 15% with highs in the 80s. Julia James, Dallas Morning News, 25 Feb. 2026 The relative humidity was increasing on Wednesday, helping ease the conditions that fueled the fire, Reynes said. ABC News, 25 Feb. 2026 Normal relative humidity for Florida’s dry season is 50% to 70%. Bill Kearney, Sun Sentinel, 25 Feb. 2026 Wind gusts may reach 55 mph, high temperatures will be in the 60s to low 70s and relative humidity levels will be as low as 10%. Jennifer McRae, CBS News, 25 Feb. 2026 See All Example Sentences for relative humidity

Word History

First Known Use

1819, in the meaning defined above

Time Traveler
The first known use of relative humidity was in 1819

Browse Nearby Words

Cite this Entry

“Relative humidity.” Merriam-Webster.com Dictionary, Merriam-Webster, https://www.merriam-webster.com/dictionary/relative%20humidity. Accessed 10 Mar. 2026.

Kids Definition

relative humidity

noun
: the amount of water vapor actually present in the air compared to the greatest amount possible at the same temperature

Medical Definition

relative humidity

noun
: the ratio of the amount of water vapor actually present in the air to the greatest amount possible at the same temperature compare absolute humidity

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