Source : Webster's Revised Unabridged Dictionary (1913)

Humid \Hu"mid\, a. [L. humidus, umidus, fr. humere, umere, to be
   moist; akin to uvidus moist, Gr. ?, Skr. uksh to wet,
   sprinkle, and Icel. v["o]kr moist, and perh. to E. ox: cf. F.
   humide.]
   Containing sensible moisture; damp; moist; as, a humidair or
   atmosphere; somewhat wet or watery; as, humid earth;
   consisting of water or vapor.

         Evening cloud, or humid bow.             --Milton.

Source : WordNet®

humid
     adj : containing or characterized by a great deal of water vapor;
           "humid air"; "humid weather"