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Synonyms

foul

American  
[faul] / faʊl /

adjective

  • fouler,
    comparative
  • foulest
    superlative
  1. grossly offensive to the senses; disgustingly loathsome; noisome.

    a foul smell.

    Synonyms:
    repellent, repulsive
    Antonyms:
    pleasant
  2. containing or characterized by offensive or noisome matter.

    foul air; foul stagnant water.

    Synonyms:
    stinking, putrid, fetid
  3. filthy or dirty, as places, receptacles, clothes, etc.

    Synonyms:
    impure, polluted, unclean
    Antonyms:
    clean
  4. muddy, as a road.

  5. clogged or obstructed with foreign matter.

    a foul gas jet.

    Antonyms:
    clear
  6. unfavorable or stormy.

    foul weather.

    Synonyms:
    tempestuous, rainy
    Antonyms:
    clear
  7. contrary, violent, or unfavorable, as the wind.

    Synonyms:
    adverse
  8. grossly offensive in a moral sense.

  9. abominable, wicked, or vile, as deeds, crime, slander, etc.

    Synonyms:
    infamous, shameful, base
  10. scurrilous, profane, or obscene; offensive.

    foul language.

    Synonyms:
    low, coarse, vulgar, smutty
  11. contrary to the rules or established usages, as of a sport or game; unfair.

    a foul blow.

  12. Baseball. pertaining to a foul ball or a foul line.

  13. limited in freedom of movement by obstruction, entanglement, etc..

    a foul anchor.

  14. abounding in errors or in marks of correction, as a printer's proof, manuscript, or the like.

  15. Nautical.

    1. (of the underwater portion of a hull) encrusted and impeded with barnacles, seaweed, etc.

    2. (of a mooring place) involving inconveniences and dangers, as of colliding with vessels or other objects when swinging with the tide.

    3. (of the bottom of a body of water) affording a poor hold for an anchor (opposed to clean).

  16. North England and Scot.. not fair; ugly or unattractive.

  17. Obsolete. disfigured.


adverb

  1. in a foul manner; vilely; unfairly.

  2. Baseball. into foul territory; so as to be foul.

    It looked like a homer when he hit it, but it went foul.

noun

  • fouls
    plural
  1. something that is foul.

  2. a collision or entanglement.

    a foul between two racing sculls.

  3. a violation of the rules of a sport or game.

    The referee called it a foul.

  4. Baseball. foul ball.

verb (used with object)

  • fouls,
    present (3rd person singular)
  • fouled,
    past participle,  past
  • fouling
    present participle
  1. to make foul; defile; soil.

    Synonyms:
    pollute, taint, besmirch, dirty, stain, sully
    Antonyms:
    clean
  2. to clog or obstruct, as a chimney or the bore of a gun.

  3. to collide with.

  4. to cause to become entangled or caught, as a rope.

  5. to defile; dishonor; disgrace.

    His reputation had been fouled by unfounded accusations.

    Synonyms:
    shame
  6. Nautical. (of barnacles, seaweed, etc.) to cling to (a hull) so as to encumber.

  7. Baseball. to hit (a pitched ball) foul (often followed by off oraway ).

    He fouled off two curves before being struck out on a fastball.

verb (used without object)

  • fouls,
    present (3rd person singular)
  • fouled,
    past participle,  past
  • fouling
    present participle
  1. to become foul.

  2. Nautical. to come into collision, as two boats.

  3. to become entangled or clogged.

    The rope fouled.

  4. Sports. to make a foul play; give a foul blow.

  5. Baseball. to hit a foul ball.

verb phrase

  1. foul up to cause confusion or disorder; bungle; spoil.

  2. foul out

    1. Baseball. to be put out by hitting a foul ball caught on the fly by a player on the opposing team.

    2. Basketball. to be expelled from a game for having committed more fouls than is allowed.

idioms

  1. run foul / afoul of, to come into collision or controversy with.

    to run foul of the press.

  2. foul one's nest, to dishonor one's own home, family, or the like.

  3. fall foul / afoul of,

    1. to collide with, as ships.

    2. to come into conflict with; quarrel.

    3. to make an attack; assault.

foul British  
/ faʊl /

adjective

  1. offensive to the senses; revolting

  2. offensive in odour; stinking

  3. charged with or full of dirt or offensive matter; filthy

  4. (of food) putrid; rotten

  5. morally or spiritually offensive; wicked; vile

  6. obscene; vulgar

    foul language

  7. not in accordance with accepted standards or established rules; unfair

    to resort to foul means

  8. (esp of weather) unpleasant or adverse

  9. blocked or obstructed with dirt or foreign matter

    a foul drain

  10. entangled or impeded

    a foul anchor

  11. (of the bottom of a vessel) covered with barnacles and other growth that slow forward motion

  12. informal unsatisfactory or uninteresting; bad

    a foul book

  13. archaic ugly

"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

noun

  1. sport

    1. a violation of the rules

    2. ( as modifier )

      a foul shot

      a foul blow

  2. something foul

  3. an entanglement or collision, esp in sailing or fishing

"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

verb

  1. to make or become dirty or polluted

  2. to become or cause to become entangled or snarled

  3. (tr) to disgrace or dishonour

  4. to become or cause to become clogged or choked

  5. (tr) nautical (of underwater growth) to cling to (the bottom of a vessel) so as to slow its motion

  6. (tr) sport to commit a foul against (an opponent)

  7. (tr) baseball to hit (a ball) in an illegal manner

  8. (intr) sport to infringe the rules

  9. (tr) (of an animal, especially a dog) to defecate on

    do not let your dog foul the footpath

  10. to collide with (a boat, etc)

"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

adverb

  1. in a foul or unfair manner

    1. to come into conflict with

    2. nautical to come into collision with

"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
foul More Idioms  

    More idioms and phrases containing foul


Synonym Usage

See dirty.

Other Word Forms

Derived Forms

Inflected Forms

Nouns

Adjectives

Participles

Conjugated Forms

Present

Past

Future


Etymology

Origin of foul

before 900; (adj. and noun) Middle English ful, foul, Old English fūl; cognate with Gothic fuls, Old Norse fūll, Old High German fūl; akin to Latin pūs pus, pūtēre to stink, Greek pýon pus; (adv.) Middle English fule, foule, derivative of the adj.; (v.) Middle English fulen, derivative of the adj.


Explanation

Foul is most commonly used as an adjective to describe a bad smell. As a verb, foul usually means “make dirty or messy.” You might foul your room to the point where it smells a bit foul. In general, foul can be used as an adjective meaning "bad." Foul luck is bad luck; a foul day is a bad day. As a verb, foul can mean "break the rules." It’s used this way in sports, like when you commit a foul on the basketball court. The phrase "foul play" can be used in the context of sports or more generally, to indicate unfair or violent behavior. Avoid confusing foul with fowl, which refers to birds, especially chickens.

Keep Reading on Vocabulary.com

Vocabulary lists containing foul

Example Sentences

Examples are provided to illustrate real-world usage of words in context. Any opinions expressed do not reflect the views of Dictionary.com.

See Examples For:

Jake LaRavia picked up his fourth foul with eight minutes and two seconds left in the second quarter.

From Los Angeles Times ● Nov. 5, 2026

Shirt pulling is not in itself an automatic foul.

From BBC ● Nov. 2, 2026

In the midst of the barnstorming action, the victors had three bad snaps on extra points and 18 penalties, including six personal foul calls.

From Los Angeles Times ● Oct. 31, 2026

Most ingeniously, Cole decided that foul balls caught by fans were recorded as outs—a heretical breaking of the fourth wall that became a Banana Ball staple.

From The Wall Street Journal ● Oct. 27, 2026

“Eureka!” cried the children, for their bubbling liquid had turned a rich shade of brown, and the foul smell of the laboratory was rapidly giving way to a fragrance that was deliciously sweet.

From "The Interrupted Tale" by Maryrose Wood

Each team was called for 12 fouls in the first half.

From Los Angeles Times ● Nov. 5, 2026

He committed two fouls during the cameo appearance and the Lakers’ six-point lead at the end of the first quarter turned into a two-point deficit by the time Looney subbed out.

From Los Angeles Times ● Oct. 28, 2026

John McGinn bought a bunch of fouls; Oli McBurnie battled hard in what McGinn called a "thankless task"; there were some fleeting moments when the crowd got energised and hope, or perhaps delusion, took hold.

From BBC ● Sep. 29, 2026

Fox’s coverage pivoted from hard fouls to trans panic, Clark got dragged into a fight she has spent three years trying to avoid and Cunningham’s follower count exploded.

From Salon ● Aug. 15, 2026

He wanted Ben to get the ball and drive straight toward Sanders, trying to draw the fourth and fifth fouls.

From "The Great Santini" by Pat Conroy

In the past, winks at some of the fouler ideas out there was enough to titillate the audience while keeping up the pretense of respectability.

From Salon ● Nov. 2, 2026

Having inured himself to the fouler demands of his job, Jovan must now contend with a more depraved, bleach-resistant form of refuse as a rogue insider splatters his workplace with sinister graffiti.

From New York Times ● Nov. 22, 2017

"Foul as it is, Hell itself is made fouler by the presence of John."

From BBC ● Oct. 18, 2016

The spirit of Marc Bolan is banished and a fouler one installed.

From The Guardian ● Jan. 12, 2016

Stones and dung and fouler things whistled overhead.

From "A Clash of Kings" by George R.R. Martin

They gave off one of the foulest smells I have ever experienced.

From BBC ● Dec. 20, 2023

Many have experienced its foulest moods and nowadays can even record what they’ve seen on their smartphones, then share the footage online.

From National Geographic ● Dec. 15, 2023

Now imagine Lennon has steered your ship safely through a horrific storm, lashing himself to the captain’s chair and singing “the foulest, filthiest, manliest sea shanty” through the night.

From Washington Post ● Dec. 21, 2018

In the early 1980s, I bartended at an Edward Gorey exhibit at New York’s Gotham Book Mart, serving some of the foulest red wine known to humankind.

From Seattle Times ● Nov. 23, 2018

That M. Dupont's arrived in the foulest mood imaginable.

From "The Remains of the Day" by Kazuo Ishiguro

Neither book argues for a return to the olfactory world of the past, and surely nobody wants streets where sewage runs in the gutters and rivers are fouled by industrial waste.

From The Wall Street Journal ● Oct. 30, 2026

Kessler then went to work on the boards, grabbing an offensive rebound and scoring on a reverse layup while being fouled by Brook Lopez.

From Los Angeles Times ● Oct. 24, 2026

He fouled off Snell’s fastball, changeup, curveball and slider.

From The Wall Street Journal ● Oct. 15, 2026

The average fastball in this postseason: 96.2 mph, according to analyst Mike Petriello’s close-up of all the different ways Ohtani’s swing is fouled up.

From Los Angeles Times ● Oct. 14, 2026

Jimmy held his hand up because he had fouled the guy.

From "Slam!" by Walter Dean Myers

The discovery was especially surprising because the buildup of material inside membrane pores, known as fouling, is normally considered a serious problem.

From Science Daily ● Nov. 5, 2026

And after De Paula had worked a full count, swinging at a pair of fastballs and fouling off the second, he sent a slider to right field.

From Los Angeles Times ● Sep. 12, 2026

Adrien Rabiot: Lucky to stay on the pitch after fouling Ruiz having already been booked for an early challenge on Dani Olmo.

From BBC ● Jul. 14, 2026

For days before their brutal and bloody round-of-16 match against Paraguay, they devoted hours of practice time to countering soccer’s Dark Arts—trash talk, persistent fouling, and relentless physicality.

From The Wall Street Journal ● Jul. 9, 2026

The oarsmen felt ropes of kelp fouling their strokes with each pull.

From "Shipwreck at the Bottom of the World" by Jennifer Armstrong

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