- any instrument for measuring the water-vapor content of the atmosphere.
Origin of hygrometer
Dictionary.com Unabridged Based on the Random House Unabridged Dictionary, © Random House, Inc. 2018
Examples from the Web for hygrometer
It crawls forward in all weathers, like Richard Edgeworth's hygrometer.Medical Essays
Oliver Wendell Holmes, Sr.
In the instrument-screen we had a thermograph, hygrometer, and thermometers.The South Pole, Volumes 1 and 2
The dew-point is determined by means of an instrument called a hygrometer.The New Gresham Encyclopedia
The Hygrometer, invented by Mr. Daniell, gives the dew-point by inspection.
Thus the hygrometer is worthy to be studied on a hunting morning.A Cotswold Village
J. Arthur Gibbs
- any of various instruments for measuring humidity
Collins English Dictionary - Complete & Unabridged 2012 Digital Edition © William Collins Sons & Co. Ltd. 1979, 1986 © HarperCollins Publishers 1998, 2000, 2003, 2005, 2006, 2007, 2009, 2012
Word Origin and History for hygrometer
Online Etymology Dictionary, © 2010 Douglas Harper
- Any of several instruments that measure humidity. The most common type of hygrometer consists of two, side-by-side mercury or electronic thermometers, one of which has a dry bulb, and one of which has a bulb wrapped with a wet cotton or linen wick. As water evaporates from the wet bulb, it absorbs heat from the thermometer, driving down its temperature reading. The difference in temperature between the two thermometers is then used to calculate the relative humidity. This type of hygrometer is also called a psychrometer. Other hygrometers make use of the temperatures at which dew forms and disappears to calculate the relative humidity. Older hygrometers used the length of a strand of hair, which stretches when it absorbs moisture, to measure relative humidity.
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