pollutant

noun

pol·​lut·​ant pə-ˈlü-tᵊnt 

plural pollutants

: something that pollutes

especially : something (such as waste created by human activity) 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 of pollutant

• contaminant
• contamination

Examples of pollutant in a Sentence

filtered the pollutants out of the water

Recent Examples on the Web

The Crafoord Prize recognized research that helped humanity better understand how invisible pollutants reshape the visible world. —Ingmar Rentzhog, Forbes.com, 22 May 2026

With summer comes pollen, grass and mulch debris, dust, and so many other pollutants that infiltrate the inside of your home. —Paige Bennett, Better Homes & Gardens, 22 May 2026

Researchers theorized that this effect could result from removing pollutants that damage white matter in the brain. —Sanja Jelic, Verywell Health, 22 May 2026

Ethanol also releases fewer nitrogen oxides—another set of tailpipe pollutants—compared with gasoline. —Stephanie Pappas, Scientific American, 22 May 2026

Word History

First Known Use

1892, 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