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.

Definitions of foul
  1. adjective
    highly offensive; arousing aversion or disgust
    synonyms: disgustful, disgusting, distasteful, loathly, loathsome, repellant, repellent, repelling, revolting, skanky, wicked, yucky
    unpleasant or disgusting especially to the senses
  2. adjective
    offensively malodorous
    “a foul odor”
    synonyms: fetid, foetid, foul-smelling, funky, ill-scented, noisome, smelly, stinking
    ill-smelling, malodorous, malodourous, stinky, unpleasant-smelling
    having an unpleasant smell
  3. adjective
    disgustingly dirty; filled or smeared with offensive matter
    “a foul pond”
    synonyms: filthy, nasty
    dirty, soiled, unclean
    soiled or likely to soil with dirt or grime
  4. verb
    make unclean
    foul the water”
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    type of:
    begrime, bemire, colly, dirty, grime, soil
    make soiled, filthy, or dirty
  5. verb
    make impure
    synonyms: contaminate, pollute
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    infect, taint
    contaminate with a disease or microorganism
    contaminate (the environment) with waste or harmful substances
    infect (an infected cell) further or infect a cell already containing similar organisms
    affect with smut or mildew, as of a crop such as corn
    type of:
    begrime, bemire, colly, dirty, grime, soil
    make soiled, filthy, or dirty
  6. verb
    spot, stain, or pollute
    synonyms: befoul, defile, maculate
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    type of:
    attaint, disgrace, dishonor, dishonour, shame
    bring shame or dishonor upon
  7. verb
    become soiled and dirty
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    type of:
    undergo a change; become different in essence; losing one's or its original nature
  8. verb
    become or cause to become obstructed
    synonyms: back up, choke, choke off, clog, clog up, congest
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    become or cause to become unobstructed
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    gum up
    stick together as if with gum
    crap up
    become obstructed or chocked up
    block, choke up, lug, stuff
    silt, silt up
    become chocked with silt
    type of:
    block, close up, impede, jam, obstruct, obturate, occlude
    block passage through
  9. adjective
    violating accepted standards or rules
    “used foul means to gain power”
    synonyms: cheating, dirty, unsporting, unsportsmanlike
    unfair, unjust
    not fair; marked by injustice or partiality or deception
  10. adjective
    (of a baseball) not hit between the foul lines
    outside the foul lines
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    (of a baseball) hit between the foul lines
    between the first and third base lines
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  11. noun
    an act that violates the rules of a sport
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    foul ball
    (baseball) a ball struck with the bat so that it does not stay between the lines (the foul lines) that define the width of the playing field
    personal foul
    a foul that involves unnecessarily rough contact (as in basketball or football)
    technical, technical foul
    (basketball) a foul that can be assessed on a player or a coach or a team for unsportsmanlike conduct; does not usually involve physical contact during play
    type of:
    infringement, violation
    an act that disregards an agreement or a right
  12. verb
    commit a foul; break the rules
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    kick on the shins
    kick on the arms
    type of:
    participate in games or sport
  13. verb
    hit a foul ball
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    foul out
    baseball: hit a ball such that it is caught from an out in foul territory
    type of:
    cause to move by striking
  14. adjective
    characterized by obscenity
    foul language”
    synonyms: cruddy, filthy, nasty, smutty
    (of behavior or especially language) characterized by obscenity or indecency
  15. adjective
    (of a manuscript) defaced with changes
    synonyms: dirty, marked-up
    (of handwriting, print, etc.) not legible
  16. adjective
    especially of a ship's lines etc
    “a foul anchor”
    synonyms: afoul, fouled
    in a confused mass
Word Family

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