psychrometer

psy·chrom·e·ter   (sī-krŏm'ĭ-tər)    n.  An instrument that uses the difference in readings between two thermometers, one having a wet bulb and the other having a dry bulb, to measure the moisture content or relative humidity of air.

Main Entry: psy·chrom·e·ter
Pronunciation: sI-'kräm-&t-&r
Function: noun
: a hygrometer consisting essentially of twosimilar thermometers with the bulb of one being kept wet so that the cooling that results from evaporation makes it register a lower temperature than the dry one and with the difference between thereadings constituting a measure of the dryness of the atmosphere —psy·chro·met·ric /"sI-kr&-'me-trik/ adjective —psy·chrom·e·try /sI-'kräm-&-trE/ noun plural -tries

psychrometer psy·chrom·e·ter (sī-krŏm'ĭ-tər)
n.
An instrument that uses the difference in readings between thermometers specialized to measure the moisture content or relative humidity of air.

psychrometer   (sī-krŏm'ĭ-tər)  Pronunciation Key  See under hygrometer.

psychrometer

a hygrometer composed of two similar thermometers. The bulb of one thermometer is kept wet (by means of a thin, wet cloth wick) so that the cooling that results from evaporation makes it register a lower temperature than the dry-bulb thermometer. When readings are taken simultaneously, it is possible (with the use of psychrometric tables) to determine the relative humidity and dew-point temperature of the air. A decrease in the humidity of the air brings an increase in the difference between dry- and wet-bulb temperatures, called the wet-bulb depression. See also hygrometer.

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