impurity

noun

im·​pu·​ri·​ty (ˌ)im-ˈpyu̇r-ə-tē 

plural impurities

1

: something that is impure or makes something else impure

removing impurities from water

2

: the quality or state of being impure

Synonyms of impurity

• contamination
• contaminant
• pollutant

Examples of impurity in a Sentence

the impurity of the water

The syrup is strained to remove impurities.

The water is free of impurities.

Recent Examples on the Web

That concentrate requires further refining to remove impurities. — Matthew Kayser, USA Today, 21 Aug. 2026

After 15 years of experiments, Schumm’s group ended up with a recipe for solid calcium fluoride crystals, doped with little impurities of thorium 229, that looked like transparent millimeter-sized cubes. — Jacek Krywko, Scientific American, 20 Aug. 2026

Hertha cleared the technical bar to become a lower-cost domestic supplier by controlling key chemical and metallic impurities on commercial-grade equipment. — Mrigakshi Dixit, Interesting Engineering, 18 Aug. 2026

The retinol in the formula sloughs away all impurities that lead to the bumps in the first place, while vitamin E and green tea fend off any sensitivities by restoring the moisture barrier. — Mary Honkus, Glamour, 18 Aug. 2026

Word History

First Known Use

15th century, in the meaning defined at sense 1

Rhymes for impurity

• maturity
• obscurity
• security
• biosecurity
• cybersecurity
• immaturity
• insecurity
• prematurity
• purity
• surety

Kids Definition

impurity

noun

im·​pu·​ri·​ty (ˈ)im-ˈpyu̇r-ət-ē 

plural impurities

1

: the quality or state of being impure

2

: something that is impure or that makes impure

remove impurities from water

Medical Definition

impurity

noun

im·​pu·​ri·​ty (ˈ)im-ˈpyu̇r-ət-ē 

plural impurities

: something that is impure or makes something else impure