Noun
The act, process, or result of combining with nitrogen or some of its compounds.
The act or process of oxidizing nitrogen or its compounds so as to form nitrous or nitric acid.
A process of oxidation, in which nitrogenous vegetable and animal matter in the presence of air, moisture, and some basic substances, as lime or alkali carbonate, is converted into nitrates.
Source: Webster's dictionaryUrease inhibitors are used to slow the hydrolytic conversion of urea into ammonia, which is prone to evaporation as well as nitrification. Source: Internet
If the C/N is less than 15, ammonia is freed to the soil, where it may be used by bacteria which oxidise it to nitrate ( nitrification ). Source: Internet