The definition of humid is there is a lot of water vapor in the air.(adjective)
When the air feels wet, heavy and sticky, this is an example of when it is humid.
See humid in Webster's New World College Dictionary
Origin: Fr humide < L humidus < humere, altered (after humus) < umere, to be moist: see humor
See humid in American Heritage Dictionary 4
Origin: Middle English
Origin: , from Latin hūmidus
Origin: , from hūmēre, to be moist.
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