impure

Etymology

It is inherited from Middle English impure,^[2] borrowed from Latin impūrus (“not pure, unclean, filthy, foul”)^{[3][4][2][5][6]} and also borrowed from Old French impur.^[4][2][7] The OED records the French adjective from the 13th century and gives only the Latin as the source,^[3] and Barnhart, who prefers Middle French, adds that the word was probably also formed in Middle English from im- and pure.^[8] The Latin adjective is formed from in- (“not”) and pūrus (“pure, clean”).^[3][4][5]

Earliest recorded meaning

Of wine, muddy, not clear: about 1440, in the Middle English Palladius, which says that seven pine kernels clear a measure of wine that is impure.^[2][4] Barnhart dates it to probably 1440,^[8] and the Shorter Oxford and the Oxford Dictionary of English to late Middle English;^[9][10] Dictionary.com gives 1530–40,^[11] and the OED's first record is from about 1533.^[3]

Semantic evolution

After the wine of the first record, the Middle English word also described love that was earthly and not spiritual.^[2][4] From the 1530s it was applied to moral stain, to people and later to acts: unchaste, lewd, defiled by sin.^[3][4] Physical dirt followed in the 1590s, and religious uncleanness in 1623.^[3][4] In the 1620s the word began to mean simply mixed with something else, without any idea of foulness,^[4][3] and it was soon used of language containing foreign idioms and later of colours.^[3] Johnson (1755) listed "unholy", "unchaste" and "foul with extraneous mixtures".^[12] As a noun, impure meant an unchaste person from 1784,^[3][4] and Green's Dictionary of Slang records it for a prostitute in the same decade, with a stage direction of 1781 using it attributively.^[13]

Timeline

• c. 1440 – of wine, muddy, not clear.^[2][4]
• c. 1500 – earthly, not spiritual.^[4][2]
• c. 1533 – of people, morally defiled, in Tyndale.^[3][4]
• 1598 – containing offensive matter, dirty.^[3][4]
• 1598 – verb, to defile (obsolete by 1673).^[3]
• 1613 – of actions and things, morally defiled; of a language or style, containing foreign idioms.^[3]
• 1623 – not ceremonially pure.^[3]
• 1626 – of physical things, mixed with foreign matter, adulterated.^[3][4]
• 1784 – noun, an unchaste person; a prostitute.^[3][4][13]
• 1860 – of a colour, containing an admixture of another.^[3]

Meanings

Adjective

1. Mixed with something else, especially of lesser quality; adulterated or contaminated: impure copper.^[14][3]
2. Containing something dirty or harmful; foul: The village's wells held impure water.^[7][3]
3. Morally stained; unchaste or lewd: impure thoughts.^[7][3]
4. In some religions, ritually unclean, and so barred from certain ceremonies or uses.^[14][7][3]
5. Of a colour, mixed with another colour or with black or white.^[14][3]
6. Of a language or style, marked by foreign elements or by incorrect or unidiomatic usage.^[7][3]
7. Of more than one origin or style, as in architecture.^[14]

Noun

1. An unchaste person; in slang, a prostitute.^[13][3]

Verb

1. (obsolete, 1598–1673) To make impure; to defile.^[7][3]

Word family

• impurely
• impureness

Related words

• impurity
• pure

References

1. ^ Wiktionary, the free dictionary, https://en.wiktionary.org
2. ^ a b c d e f g Kurath, Hans; Kuhn, Sherman M.; Lewis, Robert E., eds. (1952–2001), Middle English Dictionary, Ann Arbor: University of Michigan Press; online edition ed. Frances McSparran et al. (2000–2018)
3. ^ a b c d e f g h i j k l m n o p q r s t u v w x y Oxford English Dictionary Online (accessed March 2026), Oxford: Oxford University Press
4. ^ a b c d e f g h i j k l m n o Harper, Douglas. Online Etymology Dictionary, https://www.etymonline.com
5. ^ a b Klein, Ernest. A Comprehensive Etymological Dictionary of the English Language. 2 vols. Amsterdam: Elsevier, 1966–1967.
6. ^ Hoad, T. F., ed. (1986), The Concise Oxford Dictionary of English Etymology, Oxford: Clarendon Press
7. ^ a b c d e f Merriam-Webster Unabridged Dictionary (2024), online ed., Springfield, Mass.: Merriam-Webster
8. ^ a b Barnhart, Robert K. (1988), The Barnhart Dictionary of Etymology
9. ^ Shorter Oxford English Dictionary on Historical Principles (2002), 5th ed., ed. William R. Trumble and Angus Stevenson, Oxford: Oxford University Press
10. ^ Stevenson, Angus, ed. (2010), Oxford Dictionary of English, 3rd ed., Oxford: Oxford University Press
11. ^ Dictionary.com Unabridged (2016), based on the Random House Unabridged Dictionary, New York: Random House
12. ^ Johnson, Samuel (1755), A Dictionary of the English Language, London; 4th ed. 1773; Johnson's Dictionary Online, ed. Beth Rapp Young et al.
13. ^ a b c Green, Jonathon (2010), Green's Dictionary of Slang, London: Chambers; digital ed. 2016–, https://greensdictofslang.com
14. ^ a b c d Collins English Dictionary (2023), Glasgow: HarperCollins