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

Once captured, the pollutants are converted through a natural chemical reaction into stable byproducts—CO2 into carbonates such as calcium carbonate (CaCOz) and NOx into small quantities of harmless nitrates. —Jennifer Bringle, Sourcing Journal, 14 Oct. 2025

The agency recently announced a plan to ease regulations on climate pollutants known as hydrofluorocarbons. —Sharon Lerner, ProPublica, 10 Oct. 2025

This sponge-like porosity – meaning lots of tiny holes inside – lets MOFs trap and release gases, store energy-rich fuels like hydrogen, and capture harmful pollutants. —Bohong Zhang, The Conversation, 10 Oct. 2025

The waste introduces pollutants like nitrate into drinking water and nearby rivers and lakes. —Anna Kleiber, jsonline.com, 9 Oct. 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