adjective, un·clean·er, un·clean·est.

not clean; dirty.
morally impure; evil; vile: unclean thoughts.
Chiefly Biblical. having a physical or moral blemish so as to make impure according to the laws, especially the dietary or ceremonial laws: an unclean animal; unclean persons.

Origin of unclean

before 900; Middle English unclene, Old English unclǣne. See un-1, clean
Related formsun·clean·ness, noun

Synonyms for unclean

Dictionary.com Unabridged Based on the Random House Unabridged Dictionary, © Random House, Inc. 2019

Examples from the Web for unclean

Contemporary Examples of unclean

  • First, religious texts condemn them as unclean, plus the love Westerners shower on pets made them inherently suspect.

    The Daily Beast logo
    The Lighter Side of Islam

    Neil MacFarquhar

    May 6, 2009

Historical Examples of unclean

  • The false cannot inherit the true nor the unclean the lovely.

    Weighed and Wanting

    George MacDonald

  • You shake your heads; then why do you stare at me as though I were a thing accursed and unclean?

    Fair Margaret

    H. Rider Haggard

  • But a pig is only the unclean animal—the forbidden of the prophet.

    American Notes

    Rudyard Kipling

  • It was very ugly, but very big, and the streets in front of it were narrow and unclean.

    American Notes

    Rudyard Kipling

  • Woe betide—but, was there ever such a gathering of unclean, unholy humanity?

    The Law-Breakers

    Ridgwell Cullum

British Dictionary definitions for unclean



lacking moral, spiritual, ritual, or physical cleanliness
Derived Formsuncleanness, noun
Collins English Dictionary - Complete & Unabridged 2012 Digital Edition © William Collins Sons & Co. Ltd. 1979, 1986 © HarperCollins Publishers 1998, 2000, 2003, 2005, 2006, 2007, 2009, 2012

Word Origin and History for unclean

Old English unclæne, "morally impure, defiled, unfit for food," from un- (1) "not" + clean (adj.). Literal sense of "dirty" is recorded from mid-13c.

Online Etymology Dictionary, © 2010 Douglas Harper