Source : Webster's Revised Unabridged Dictionary (1913)

Oxide \Ox"ide\, n. [F. oxyg[`e]ne oxygen + acide acid: cf. F.
   oxyde. The French word was correctly spelt oxide, till about
   the year 1840, when, in ignorance or forgetfulness of the
   true history and composition of the word, the orthography was
   change to make it represent the [upsilon] of Gr. 'oxy`s, from
   which it was supposed to be directly derived.] (Chem.)
   A binary compound of oxygen with an atom or radical, or a
   compound which is regarded as binary; as, iron oxide, ethyl
   oxide, nitrogen oxide, etc.

   Note: In the chemical nomenclature adopted by Guyton de
         Morveau, Lavoisier,and their associates, the term
         oxides was made to include all compounds of oxygen
         which had no acid (F. acide) properties, as contrasted
         with the acids, all of which were at that time supposed
         to contain oxygen. The orthography oxyde, oxyd, etc.,
         was afterwards introduced in ignorance or disregard of
         the true etymology, but these forms are now obsolete in
         English. The spelling oxid is not common.

Source : WordNet®

oxide
     n : any compound of oxygen with another element or a radical