de·ni·tri·fy 
(dē-nītrə-fī′)
(dē-nītrə-fī′)tr.v. de·ni·tri·fied, de·ni·tri·fy·ing, de·ni·tri·fies
1. To remove nitrogen or nitrogen groups from (a compound).
2. To reduce (nitrates or nitrites) to nitrogen-containing gases, as by bacterial action on soil.
de·ni′tri·fi·cation (-fĭ-kāshən) n.