relative humidity


Definition of relative humidity

: 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

The heat index is calculated through a series of equations that factor temperature and relative humidity. Jesus Jimenez, Dallas News, "Dallas-Fort Worth's heat index could reach 105 degrees this weekend — but what does that mean?," 6 June 2019 The device can harvest 2.8 liters of water daily for every kilogram of MOF even at relative humidity levels as low as 20 percent, similar to those of deserts. Donna J. Nelson, Scientific American, "Off-Grid Devices Draw Drinking Water from Dry Air," 26 June 2017 If no moisture is added, relative humidity drops as air warms. Tom Skilling,, "Ask Tom: Is air pollution factored in when measuring relative humidity?," 16 Mar. 2018 As the humidity changes, the lengthening or shrinking of the hair strands causes the hygrometer to display the current relative humidity. Tom Skilling,, "Ask Tom: Why does humid weather affect hair?," 4 May 2018 Decker can manage temperatures, relative humidity, wind speed, and natural solar radiation (minus UV rays for safety). Tim Newcomb, Popular Mechanics, "Inside the Futuristic Labs That Forge Gore-Tex," 28 Nov. 2016 The opposite is true when the relative humidity decreases because the rate of perspiration increases. Cincinnati Enquirer,, "Not a dry heat: Heat index in 100s," 18 June 2018 When the relative humidity of the atmosphere is high, there is essentially no more room in the surrounding environment for liquid, including sweat. Greg Porter, Washington Post, "PM Update: Mild and muggy tonight, oppressive heat and humidity Monday," 17 June 2018 Thus, relative humidity depends on the air temperature and its moisture content. Tom Skilling,, "Ask Tom: What does 'relative humidity' mean?," 29 May 2018

These example sentences are selected automatically from various online news sources to reflect current usage of the word 'relative humidity.' Views expressed in the examples do not represent the opinion of Merriam-Webster or its editors. Send us feedback.

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First Known Use of relative humidity

1819, in the meaning defined above

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Statistics for relative humidity

Last Updated

2 Jul 2019

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Time Traveler for relative humidity

The first known use of relative humidity was in 1819

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More Definitions for relative humidity

relative humidity


Medical Definition of relative humidity

: 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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