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

Caraballeda’s tropical, beachfront climate could have been a factor, as well as possible impurities in the concrete used, which can eat away at the metal bars. — Avery Schmitz, CNN Money, 8 Nov. 2026

The rules would apply if government testing finds the drug fails quality standards for impurities ‌or sterility, the amount of active ingredient, or dissolution, which assesses how the drug releases that ingredient. — Ed Silverman, STAT, 5 Nov. 2026

The German nuclear physicists had to use metallurgical coke from the Ruhr, which had twice as many impurities as American coke. — Jennifer Ouellette, ArsTechnica, 4 Nov. 2026

Purification removes unwanted impurities, while dehydration reduces moisture content. — Prabhat Ranjan Mishra, Interesting Engineering, 28 Oct. 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