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Synonyms

foul

American  
[foul] / 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.

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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:

That allowed the Dodgers to tie the score in the bottom of the sixth on Tommy Edman’s seventh home run of the season just inside the right-field foul pole.

From Los Angeles Times Sep. 20, 2026

At the time, Mourinho pleaded with the referee for a red card to be shown to the Argentina international for dangerous foul play, because replays showed Romero made contact with his studs on Bellingham's knee.

From BBC Sep. 20, 2026

He renders the original’s panoply of suffering in accessible English, as in this view of Satan: “With six eyes / He wept, and three chins let the foul tears fall / And bloody foam.”

From The Wall Street Journal Sep. 11, 2026

After his former protégé, Treasury Secretary Scott Bessent, said the U.S. would double repurchases of long-term bonds when they hit a previous peak, star hedge-fund manager Stanley Druckenmiller cried foul in The Wall Street Journal.

From The Wall Street Journal Sep. 10, 2026

A hot, foul wind blew down the street, clogging my throat and making my eyes water.

From "City of the Plague God" by Sarwat Chadda

Sometimes players will get involved in healthy debates about potential fouls, although on other occasions the odd player might be caught catching a nap.

From BBC Aug. 20, 2026

He played basketball for the Lions, but after his sophomore season he decided to try football, since his physical play in basketball led to fouls, something that was legal in football.

From Los Angeles Times Aug. 16, 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

Public spats over fouls and a fixation on transgender policy have overshadowed the WNBA’s rising attendance and TV audiences.

From The Wall Street Journal Aug. 14, 2026

I would soon learn that calling fouls just wasn’t done.

From "The Other Wes Moore: One Name, Two Fates" by Wes Moore

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

And his merchants and armies were making a befouled realm even fouler.

From Slate Feb. 6, 2017

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

From BBC Oct. 18, 2016

Those off-flavors are the result of breaking down secondary products like amino acids and the ethanol which might result in some fouler or vinegary compounds, such as esters and aldehydes.

From Scientific American Aug. 20, 2012

The darkness covered fouler intentions than my own.

From "Ophelia" by Lisa Klein

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

But by 1850, his family said he was a "changed man", with the former leader describing slavery as "by far the foulest crime that taints the history of mankind".

From BBC Aug. 20, 2023

“There is no greater fool than one who shouts ‘Happy Christmas!’ in a city throughout which the foulest of mankind lurks ’round every corner,” Holmes growls.

From New York Times Dec. 1, 2021

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

Jefferson was guilty of “the blackest calumny and foulest falsehoods” during that bitter campaign.

From "Founding Brothers: The Revolutionary Generation" by Joseph J. Ellis

The score, Reus’ sixth of the season and third from the penalty spot, was set up when Seattle’s Paul Rothrock fouled the Galaxy’s Hirving Lozano in the box.

From Los Angeles Times Sep. 13, 2026

After close to an hour of physical, full-blooded football, Sunderland were given a penalty when Ezri Konsa fouled Dan Ballard at a corner.

From BBC Sep. 12, 2026

Each touch of the ball was greeted by a mixture of boos and cheers, while some fans also celebrated when Fernandez was fouled.

From BBC Aug. 15, 2026

In a full count, Rushing fouled off another changeup.

From Los Angeles Times Jul. 23, 2026

Hazelwood’s Mills takes it down, under full- court pressure, and—no—he’s fouled on the shot and will go to the line for two.

From "Tears of a Tiger" by Sharon M. Draper

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

But the victory came with an asterisk: Folarin Balogun, a Brooklyn-born striker who leads the team in goals, got a red card for fouling an opposing player.

From Slate Jul. 6, 2026

Sithole's dismissal for fouling Brian Gutierrez was a simple decision for referee Wilton Sampaio.

From BBC Jun. 11, 2026

“The bottom half of the order, they were fouling off a lot of balls, we couldn’t put those guys out,” Roberts said.

From Los Angeles Times Jun. 7, 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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