nastier; nastiest
Synonyms of nasty
1
a
: disgustingly filthy
nasty living conditions
b
: physically repugnant
a nasty taste
2
: indecent, obscene
nasty language
3
: mean, tawdry
… living a cheap and nasty life …George Bernard Shaw
4
a
: extremely hazardous (see hazardous sense 1) or harmful
a nasty undertow
b
: causing severe pain or suffering
a nasty wound
a nasty fall
c
: sharply unpleasant : disagreeable
nasty weather
5
a
: difficult to understand or deal with
a nasty problem
a nasty curveball
b
: psychologically unsettling : trying
a nasty fear that she was lost
6
: lacking in courtesy or sportsmanship
a nasty trick
nasty noun
Choose the Right Synonym for nasty

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 nasty in a Sentence

She has a nasty habit of biting her fingernails. The medicine left a nasty taste in my mouth. That nasty old man yelled at me just for stepping on his lawn! He sent a nasty letter to the company. She's got quite a nasty temper. He said lots of downright nasty things about her. She called him a few nasty names and left.
Recent Examples on the Web
Examples are automatically compiled from online sources to show current usage. Read More Opinions expressed in the examples do not represent those of Merriam-Webster or its editors. Send us feedback.
Even by the famously hostile standards of New York City’s high-end co-ops, this was nasty. Noah Shachtman, Vanity Fair, 25 Aug. 2026 Top and bottom line miss, paired with a nasty cut to its full-year EPS outlook. Jim Cramer, CNBC, 25 Aug. 2026 But that’s not stopped the current and former mayors – who duked it out in what many describe as the nastiest local election in recent history – from going at it again. Denise Crosby, Chicago Tribune, 23 Aug. 2026 In addition, the short-half-life isotopes tend to get discarded by the process, and there's also the need to keep the streams of pure plutonium from concentrating, or things could get very nasty. David Szondy august 22, New Atlas, 22 Aug. 2026 See All Example Sentences for nasty

Word History

Etymology

Middle English

First Known Use

14th century, in the meaning defined at sense 1a

Time Traveler
The first known use of nasty was in the 14th century

Browse Nearby Words

Cite this Entry

“Nasty.” Merriam-Webster.com Dictionary, Merriam-Webster, https://www.merriam-webster.com/dictionary/nasty. Accessed 27 Aug. 2026.

Kids Definition

nasty

adjective
nastier; nastiest
1
: very dirty or foul : filthy
2
: morally disgusting or degrading
3
: disagreeable sense 1, unpleasant
nasty weather
4
: spiteful, ill-natured
a nasty temper
a nasty trick
5
: harmful, dangerous
a nasty fall on the ice
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