nitrifyPronunciation: /ˈnʌɪtrɪfʌɪ/Definition of nitrify verb (nitrifies, nitrifying, nitrified) [with object] Chemistry convert (ammonia or another nitrogen compound) into nitrites or nitrates: a considerable amount of the ammonia so formed is nitrifiedDerivatives nitrificationPronunciation: /-fɪˈkeɪʃ(ə)n/ noun Origin: early 19th century: from French nitrifiernitrify in other Oxford dictionaries Definition of nitrify in the US English dictionary