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adjective, nas·ty \ˈnas-tē\

Simple Definition of nasty

  • : very unpleasant to see, smell, taste, etc.

  • : indecent and offensive

  • : unpleasant and unkind

Source: Merriam-Webster's Learner's Dictionary

Full Definition of nasty


  1. 1 a :  disgustingly filthy b :  physically repugnant

  2. 2 :  indecent, obscene

  3. 3 :  mean, tawdry

  4. 4 a :  extremely hazardous or harmful <a nasty undertow> b :  causing severe pain or suffering <a nasty wound> <a nasty fall> c :  sharply unpleasant :  disagreeable <nasty weather>

  5. 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. 6 :  lacking in courtesy or sportsmanship <a nasty trick>

nastily play \-tə-lē\ adverb
nastiness play \-tē-nəs\ noun
nasty noun

Examples of nasty in a sentence

  1. She has a nasty habit of biting her fingernails.

  2. The medicine left a nasty taste in my mouth.

  3. That nasty old man yelled at me just for stepping on his lawn!

  4. He sent a nasty letter to the company.

  5. She's got quite a nasty temper.

  6. He said lots of downright nasty things about her.

  7. She called him a few nasty names and left.

Origin of nasty

Middle English

First Known Use: 14th century

Synonym Discussion of 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>.

Rhymes with nasty

NASTY Defined for Kids


adjective nas·ty \ˈna-stē\

Definition of nasty for Students


  1. 1 :  2mean 1 <He has a nasty disposition.>

  2. 2 :  very unpleasant <nasty weather> <a nasty taste>

  3. 3 :  very serious :  harmful <I had a nasty fall on the ice.>

  4. 4 :  very dirty :  filthy

  5. 5 :  indecent <nasty jokes>

nastily \ˈna-stə-lē\ adverb
nastiness \ˈna-stē-nəs\ noun

Seen and Heard

What made you want to look up nasty? Please tell us where you read or heard it (including the quote, if possible).


to dishevel or rumple

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