The Collaborative International Dictionary of English v.0.48:

Meteorology \Me`te*or*ol"o*gy\, n. [Gr. ?; ? + lo`gos discourse:
   cf. F. m['e]t['e]orologie. See Meteor.]
   The science which treats of the atmosphere and its phenomena,
   particularly of its variations of heat and moisture, of its
   winds, storms, etc.
   [1913 Webster]

WordNet (r) 3.0 (2006):

meteorology
    n 1: predicting what the weather will be [syn: meteorology,
         weather forecasting]
    2: the earth science dealing with phenomena of the atmosphere
       (especially weather)