also: エヌオーエックス
noun
nitrogen oxide; NOx
Technical term in chemistry; refers to nitrogen oxides collectively, often in the context of air pollution or combustion.
自動車の排気ガスにはＮＯｘが含まれている。
Automobile exhaust contains NOx.
工場はＮＯｘの排出量を削減する必
Factories need to reduce their NOx emissions.
From the chemical symbol NOx, where 'NO' stands for nitric oxide and 'x' indicates a variable number of oxygen atoms. The reading ノックス is a direct adaptation of the English pronunciation.