Source : Webster's Revised Unabridged Dictionary (1913)

Ammonia \Am*mo"ni*a\, n. [From sal ammoniac, which was first
   obtaining near the temple of Jupiter Ammon, by burning
   camel's dung. See {Ammoniac}.] (Chem.)
   A gaseous compound of hydrogen and nitrogen, {NH3}, with a
   pungent smell and taste: -- often called {volatile alkali},
   and {spirits of hartshorn}.

Source : WordNet®

ammonia
     n 1: a pungent gas compounded of nitrogen and hydrogen (NH3)
     2: a water solution of ammonia [syn: {ammonia water}, {ammonium
        hydroxide}]