1
a
: offensive to the senses : loathsome
the foul odor of rotten eggs
b
: filled or covered with offensive matter
foul bins of filth
2
: being odorous and impure : polluted
foul air
3
a
: morally or spiritually odious : detestable
a foul crime
b
: notably unpleasant or distressing : wretched, horrid
in a foul mood
4
: obscene, abusive
foul language
5
a
: being wet and stormy
foul weather
b
: obstructive to navigation
a foul tide
6
a
: treacherous, dishonorable
fair means or foul
b
: constituting an infringement (see infringe sense 1) of rules in a game or sport
a foul blow in boxing
7
: being outside the foul lines in baseball
… a foul fly that was snagged by a fan in the stands.E. M. Swift
8
: containing marked-up corrections
a foul manuscript
foul proofs
9
: full of dirt or mud
10
: encrusted, clogged, or choked with a foreign substance
the chimney was foul and smoked badly
11
: placed in a situation that impedes physical movement : entangled
a foul fishing line
12
dialectal British : homely, ugly
foully adverb
foulness noun

foul

2 of 4

noun

1
a
: an infringement of the rules in a game or sport
2
3
: an entanglement or collision especially in angling or sailing
4
archaic : something foul

foul

3 of 4

verb

fouled; fouling; fouls

transitive verb

1
: to make foul: such as
a
: to make dirty : pollute
b
: to tangle or come into collision with
c
: to encrust with a foreign substance
a ship's bottom fouled with barnacles
2
3
: to commit a foul against
4
: to hit (a baseball) foul

intransitive verb

1
: to commit a violation of the rules in a sport or game
2
: to hit a foul ball
3
: to become or be foul: such as
a
b
: to become encrusted, clogged, or choked with a foreign substance
c
: to become entangled or come into collision

foul

4 of 4

adverb

: in a foul manner : so as to be foul
Choose the Right Synonym for foul

dirty, filthy, foul, nasty, squalid mean conspicuously unclean or impure.

dirty emphasizes the presence of dirt more than an emotional reaction to it.

a dirty littered street

filthy carries a strong suggestion of offensiveness and typically of gradually accumulated dirt that begrimes and besmears.

a stained greasy floor, utterly filthy

foul implies extreme offensiveness and an accumulation of what is rotten or stinking.

a foul-smelling open sewer

nasty applies to what is actually foul or is repugnant to one expecting freshness, cleanliness, or sweetness.

it's a nasty job to clean up after a sick cat

In practice, nasty is often weakened to the point of being no more than a synonym of unpleasant or disagreeable.

had a nasty fall
his answer gave her a nasty shock

squalid adds to the idea of dirtiness and filth that of slovenly neglect.

squalid slums

All these terms are also applicable to moral uncleanness or baseness or obscenity.

dirty then stresses meanness or despicableness

don't ask me to do your dirty work

, while filthy and foul describe disgusting obscenity or loathsome behavior

filthy street language
a foul story of lust and greed

, and nasty implies a peculiarly offensive unpleasantness.

a stand-up comedian known for nasty humor

Distinctively, squalid implies sordidness as well as baseness and dirtiness.

engaged in a series of squalid affairs

Examples of foul in a Sentence

Adjective the foul odor of rotten eggs The medicine left a foul taste in my mouth. The weather has been foul all week. Noun He hit several fouls in a row. Verb pollutants that foul the air She fouled on her first long jump attempt. He was fouled as he attempted the shot. He kept fouling pitches into the stands.
Recent Examples on the Web
Adjective
Blackburn that got Garcia on a foul pop for the third out. Jerry McDonald, The Mercury News, 13 Apr. 2024 Point guard Isaiah Fuller leads NSU in assists (3.4) and foul shooting (84.7). Walter Villa, Miami Herald, 29 Mar. 2024 See all Example Sentences for foul 

These examples are programmatically compiled from various online sources to illustrate current usage of the word 'foul.' Any opinions expressed in the examples do not represent those of Merriam-Webster or its editors. Send us feedback about these examples.

Word History

Etymology

Adjective and Noun

Middle English, from Old English fūl; akin to Old High German fūl rotten, Latin pus pus, putēre to stink, Greek pyon pus

First Known Use

Adjective

before the 12th century, in the meaning defined at sense 1a

Noun

before the 12th century, in the meaning defined at sense 4

Verb

before the 12th century, in the meaning defined at intransitive sense 1

Adverb

13th century, in the meaning defined above

Time Traveler
The first known use of foul was before the 12th century

Dictionary Entries Near foul

Cite this Entry

“Foul.” Merriam-Webster.com Dictionary, Merriam-Webster, https://www.merriam-webster.com/dictionary/foul. Accessed 2 May. 2024.

Kids Definition

foul

1 of 4 adjective
1
a
: disgusting in looks, taste, or smell
foul odor
b
: full of or covered with dirt
foul clothes
2
a
: detestable
a foul crime
b
: notably unpleasant or bad
a foul mood
c
: being vulgar or insulting
foul language
3
: being wet and stormy
foul weather
4
a
: very unfair
fair means or foul
b
: breaking a rule in a game or sport
a foul blow in boxing
5
: being outside the foul lines in baseball
a foul grounder
foully adverb
foulness
ˈfau̇(ə)l-nəs
noun

foul

2 of 4 noun
1
: an entanglement or collision in fishing or sailing
2
a
: a breaking of the rules in a game or sport
3

foul

3 of 4 verb
1
: to make or become foul or filthy
foul the air
foul a stream
2
a
: to make a foul in a game or sport
b
: to hit a foul ball
3
: to become or cause to become entangled
foul the lines

foul

4 of 4 adverb
: in a foul manner : so as to be foul

More from Merriam-Webster on foul

Last Updated: - Updated example sentences
Love words? Need even more definitions?

Subscribe to America's largest dictionary and get thousands more definitions and advanced search—ad free!