Nitrification

Part of speech: noun (n.)

1. The act, process, or result of combining with nitrogen or some of its compounds.

2. The act or process of oxidizing nitrogen or its compounds so as to form nitrous or nitric acid.

3. 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.