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adjective \ˈklēn\

Simple Definition of clean

  • : free from dirt, marks, etc. : not dirty

  • : tending to keep clean

  • : free from pollution or other dangerous substances

Full Definition of clean

  1. 1 a :  free from dirt or pollution <changed to clean clothes> <clean solar energy> b :  free from contamination or disease <a clean wound> c :  free or relatively free from radioactivity <a clean atomic explosion>

  2. 2 a :  unadulterated, pure <the clean thrill of one's first flight> b of a precious stone :  having no interior flaws visible c :  free from growth that hinders tillage <clean farmland>

  3. 3 a :  free from moral corruption or sinister connections of any kind <a candidate with a clean record>; also :  free from violations <a clean driving record> b :  free from offensive treatment of sexual subjects and from the use of obscenity <a clean joke> c :  observing the rules :  fair <a clean fight>

  4. 4 :  ceremonially or spiritually pure <and all who are clean may eat flesh — Leviticus 7:19(Revised Standard Version)>

  5. 5 a :  thorough, complete <a clean break with the past> b :  deftly executed :  skillful <clean ballet technique> c :  hit beyond the reach of an opponent <a clean single to center>

  6. 6 a :  relatively free from error or blemish :  clear; specifically :  legible <clean copy> b :  unencumbered <clean bill of sale>

  7. 7 a :  characterized by clarity and precision :  trim <a clean prose style> <architecture with clean almost austere lines> b :  even, smooth <a clean edge> <a sharp blow causing a clean break> c :  free from impedances to smooth flow (as of water or air) <a clean airplane> <a ship with a clean bottom>

  8. 8 a :  empty <the ship returned with a clean hold> b :  free from drug addiction <has been clean for six months> c slang :  having no contraband (as weapons or drugs) in one's possession

  9. 9 :  habitually neat

clean·ness play \ˈklēn-nəs\ noun

Examples of clean

  1. This table isn't clean. There's a sticky spot where something spilled.

  2. He keeps a very clean house.

  3. The janitor does a good job of keeping the office clean.

  4. I wiped the baby's face clean.

  5. He's a clean young man.

  6. Cats are very clean animals.

  7. Solar power provides clean energy.

Origin of clean

Middle English clene, from Old English clǣne; akin to Old High German kleini delicate, dainty

First Known Use: before 12th century




Simple Definition of clean

  • : all the way : completely or entirely

Full Definition of clean

  1. 1 a :  so as to clean <a new broom sweeps clean> b :  in a clean manner <play the game clean>

  2. 2 :  all the way :  completely <the bullet went clean through his arm>

Examples of clean

  1. Somehow, the top of the machine came clean off.

  2. The nail went clean through the wall.

  3. The fish were jumping clean out of the water.

Before 12th Century

First Known Use of clean

before 12th century




Simple Definition of clean

  • : to make (something) clean : to remove dirt, marks, etc., from (something)

  • : to become clean

  • : to make (something, such as a room) neat and orderly

Full Definition of clean

  1. transitive verb
  2. 1 a :  to make clean: as (1) :  to rid of dirt, impurities, or extraneous matter (2) :  to rid of corruption <vowing to clean up city hall> b :  remove, eradicate —usually used with up or off <clean up that mess>

  3. 2 a :  strip, empty <a tree cleaned of fruit> b :  to remove the entrails from <clean fish> c :  to deprive of money or possessions —often used with out <they cleaned him out completely>

  4. intransitive verb
  5. :  to undergo or perform a process of cleaning <clean up before dinner>

clean·abil·i·ty play \ˌklē-nə-ˈbi-lə-tē\ noun
clean·able play \ˈklē-nə-bəl\ adjective
clean house
  1. 1 :  to clean a house and its furniture

  2. 2 :  to make sweeping reforms or changes (as of personnel)

clean one's clock
  1. :  to beat one badly in a fight or competition

clean up one's act
  1. :  to behave in a more acceptable manner

Examples of clean

  1. The carpet needs to be cleaned.

  2. They divide household duties so that she cleans and her husband cooks.

  3. They cleaned the fish and cooked them on the campfire.

  4. skin and clean a rabbit

15th Century

First Known Use of clean

15th century




Simple Definition of clean

  • : an act of removing dirt from something

Full Definition of clean

  1. :  an act of cleaning dirt especially from the surface of something

Circa 1889

First Known Use of clean

circa 1889

Seen and Heard

What made you want to look up clean? Please tell us where you read or heard it (including the quote, if possible).


February 11, 2016

the holder of an office

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