Humidity is how much invisible water the air is carrying. High humidity, the humidity is unbearable, relative humidity.
Relative humidity is the figure in weather forecasts and means how close the air is to holding all the water it can at that temperature — which is why the same amount of water gives different readings on hot and cold days. High humidity makes heat feel worse because sweat evaporates more slowly. Note humid, the adjective; humidifier and dehumidifier; and that damp and humid are not the same.
1nounhumidityHow much water vapour the air is carrying.
“The humidity in the jungle made our clothes damp and sticky.”
humidity is a measure of moisture.
Latin umidus means moist, from umere, to be wet. The h in the English spelling was added by medieval writers who wrongly connected it to humus, the earth — so the h is a mistake about eight hundred years old.
Latin
ūmidus — damp, moist, wet
Medieval Latin
hūmiditās
Old French
humidité
Middle English
humidite
English, today
humidity
From Middle English humidite, borrowed from Old French humidité, from Medieval Latin hūmiditās, from Latin ūmidus (“damp, moist, wet”). by surface analysis, humid + -ity.
Etymology from Wiktionary, CC BY-SA