Air pollutant refers to any gas, particle or substance present in the air that has damaging effects on human health, animals or the environment. There are several synonyms for air pollutant that are commonly used in the scientific community and in day-to-day conversations. Some of the synonyms for air pollutant include particulate matter (PM), ozone, smog, carbon monoxide, sulfur dioxide, nitrogen oxide, volatile organic compounds (VOCs), and heavy metals. These synonyms are useful for understanding the different types of air pollutants and their sources, as well as for developing effective strategies to reduce their impact on human health and the environment.