impure

adjective

im·​pure (ˌ)im-ˈpyu̇r 

: not pure: such as

a

: containing something unclean : foul

impure water

b

: mixed or impregnated with an extraneous and usually unwanted substance

an impure chemical

c

: lewd, unchaste

d

: ritually unclean

impurely adverb

impureness noun

Synonyms

• adulterate
• adulterated
• alloyed
• contaminated
• dilute
• diluted
• polluted
• tainted
• thinned
• weakened

Examples of impure in a Sentence

be careful, because impure motor oil can damage your car's engine

Victorian notions of what qualified as impure art now strike us as laughable.

Recent Examples on the Web

Farmers or middlemen also frequently adulterated milk, watering it down to stretch supplies—with impure water likely to introduce further pathogens—or adding toxic substances, like formaldehyde or chalk, meant to conceal spoilage or make milk appear whiter. — Made By History, Time, 29 Apr. 2025

What was considered holy at one time was considered impure in other epochs. —Isaac Bashevis Singer, Harpers Magazine, 26 Mar. 2025

In any case, playing Bach on a concert grand is an inherently impure act; Bach knew of no such instrument. —Alex Ross, The New Yorker, 10 Mar. 2025

In any case, playing Bach on a concert grand is an inherently impure act; Bach knew of no such instrument. —Alex Ross, The New Yorker, 10 Mar. 2025

Word History

Etymology

Middle English, from Middle French & Latin; Middle French, from Latin impurus, from in- + purus pure

First Known Use

15th century, in the meaning defined above

Rhymes for impure

• abjure
• adjure
• allure
• assure
• brochure
• cocksure
• coiffure
• contour
• couture
• demure
• detour
• endure

Kids Definition

impure

adjective

im·​pure (ˈ)im-ˈpyu̇(ə)r 

1

: not pure : unclean, dirty

2

: mixed with something else that is usually not as good

an impure chemical

impurely adverb

Medical Definition

impure

adjective

im·​pure (ˈ)im-ˈpyu̇(ə)r 

: not pure: as

a

: containing something unclean

impure water

b

: mixed or impregnated with an extraneous and usually unwanted substance : adulterated

an impure chemical