Definition of "psychrometer" []

• 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. (noun)

American Heritage(R) Dictionary of the English Language, Fifth Edition. Copyright (c) 2011 by Houghton Mifflin Harcourt Publishing Company. Published by Houghton Mifflin Harcourt Publishing Company. All rights reserved.

• "Twelve ordinary standard (psychrometer -) thermometers, divided to fifths of a degree (Centigrade)."
• "Temperature and humidity readings have been collected using a sling psychrometer, a simple device containing two mercury thermometers."
• "Where most unstaffed weather stations have undergone technology upgrades, consistent use of the sling psychrometer has helped provide scientific precision to the Mount Washington climate record."