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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Mold begins to grow once your home reaches 60 percent relative humidity. Brandee Gruener, Southern Living, 28 May 2026 Winds are expected to be west-southwest 20 to 30 mph with gusts up to 40 mph and minimum relative humidity between 10-15%. Ca Weather Bot, Sacbee.com, 23 May 2026 Sustained winds of 25 to 30 mph, gusts up to 50 mph and relative humidity under 10% will combine with dry fuels causing any fires that ignite to spread at a life-threatening pace, according to the National Weather Service. Taylor Ward, CNN Money, 17 May 2026 Gusts up to 50 mph are possible with relative humidity as low as 8%. Callie Zanandrie, CBS News, 17 May 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 31 May. 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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