Noxious fumes continuously drift into our windows from the factory nearby.
noxa (injury, hurt) (Latin)
Oxides of nitrogen are all toxic and are represented by NOx (Sulfur oxides by SOx)so NOx -IOUS. means harmful. also something NOXIOUS can make you NAUSEOUS NOXIOUS=TOXIOUS. harmful Noxious [Naxalites - bihar ke harmul, injurious terrorist] (Naxalites are Harmful terrorist of Bihar, India)