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

• polluted
• contaminated
• dilute
• diluted
• thinned
• adulterated

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

France has Europe’s largest population of Muslims, over 6 million, for whom pigs are considered impure. —Reuters, CNN Money, 9 Sep. 2025

Even the most natural parts of many women’s lives — such as menstruation, clothing or even breastfeeding — can be framed as being impure or as moral transgressions. —Mark Travers, Forbes.com, 5 Sep. 2025

This method combines impure raw silicon with pure aluminum, lowering the melting temperature compared to conventional polysilicon production. —Jijo Malayil, Interesting Engineering, 12 Aug. 2025

Water was often impure, too, especially with the war going on. —Doug Ross, Chicago Tribune, 10 June 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