Source : Webster's Revised Unabridged Dictionary (1913)

Oxidation \Ox`i*da"tion\, n. [Cf. F. oxidation.] (Chem.)
   The act or process of oxidizing, or the state or result of
   being oxidized.

Source : WordNet®

oxidation
     n : the process of oxidizing; the addition of oxygen to a
         compound with a loss of electrons; always occurs
         accompanied by reduction [syn: {oxidization}, {oxidisation}]