pollution

noun

pol·​lu·​tion pə-ˈlü-shən 

1

a

: the action of polluting

especially : the action of making an environment unsuitable or unsafe for use by introducing chemical or manufacturing waste

Abandoned mining and milling operations are already implicated in pollution of the river with toxic and radioactive waste products …

—Larry Brown

b

: the condition of being polluted

A three-year study … has indicated that the lake already is suffering from severe pollution and that any additional development will exacerbate it.

—Anthony DePalma

2

: something that pollutes

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

tested the levels of pollution [=pollutants] in the water

Examples of pollution in a Sentence

industrial practices that have caused pollution of the air and water

The tests showed high levels of pollution in the water.

The fish are dying of pollution.

Recent Examples on the Web

Once home to thriving populations of the state's iconic staghorn and elkhorn corals, the ecosystem has been in steady decline for decades because of pollution, disease, invasive species, warming waters, and damage from boaters, divers and snorkelers. —Arkansas Online, 8 Mar. 2026

The Iranian Red Crescent Society warned Tehran residents to take precautions against toxic air pollution and the risk of acid rain. —Dallas Morning News, 8 Mar. 2026

Earlier on Sunday, Iran’s Red Crescent Society released a statement warning residents not to leave their homes because of high levels of toxic pollution caused by the strike on the fuel depots. —Golnar Motevalli, Fortune, 8 Mar. 2026

Fertilizer runoff from lawns is a major source of nutrient pollution in lakes and streams. —Kim Toscano, Southern Living, 7 Mar. 2026

Word History

First Known Use

14th century, in the meaning defined at sense 1a

Phrases Containing pollution

• light pollution
• noise pollution
• thermal pollution

Rhymes for pollution

• ablution
• aleutian
• confucian
• dilution
• elution
• locution
• solution
• volution
• absolution
• allocution
• attribution
• comminution

Kids Definition

pollution

noun

pol·​lu·​tion pə-ˈlü-shən 

1

: the action of polluting : the state of being polluted

air pollution

compare noise pollution, thermal pollution

2

: pollutant

Medical Definition

pollution

noun

pol·​lu·​tion pə-ˈlü-shən 

1

: the action of polluting or the condition of being polluted

2

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