pollutant

noun

pol·​lut·​ant pə-ˈlü-tᵊnt 

plural pollutants

: something that pollutes

especially : something (such as anthropogenic waste) that makes an environment unsuitable or unsafe for use

sources of pollutants [=pollution] in the environment

Meanwhile, scientists warned that other air pollutants—especially from automobiles—might also be contributing to health problems, forest damage and decreased crop production.

—National Wildlife

Formaldehyde is an important atmospheric pollutant that can be produced in photochemical smog.

—Des W. Connell

A 165-foot cement tower contains radium-rich blends that have given off radon gas—a pollutant that can cause cancer.

—Michael H. Brown

Synonyms

• contaminant
• contamination

Examples of pollutant in a Sentence

filtered the pollutants out of the water

Recent Examples on the Web

Because of Memphis' history of exceptionally poor air quality, any new source of pollutants requires permitting and emissions testing. —ArsTechnica, 18 June 2025

People who may be especially sensitive to the effects of elevated levels of pollutants include the very young and those with preexisting respiratory problems such as asthma or heart disease. —Kansas City Star Weather Bot, Kansas City Star, 18 June 2025

When air is stagnant, pollutants don't get dispersed, allowing ozone to build up to unhealthy levels. —Joe Edwards, MSNBC Newsweek, 17 June 2025

Common causes of brown phlegm include smoking, exposure to toxins or pollutants in the air, cystic fibrosis, and bacterial lung infections. —Mark Gurarie, Health, 15 June 2025

Word History

First Known Use

1887, in the meaning defined above

Rhymes for pollutant

• disputant
• mutant

Kids Definition

pollutant

noun

pol·​lut·​ant pə-ˈlüt-ᵊnt 

: something that pollutes

Medical Definition

pollutant

noun

pol·​lut·​ant pə-ˈlüt-ᵊnt 

: something that pollutes

especially : something (such as anthropogenic waste) that makes an environment unsuitable or unsafe for use