nasty

¹ American  

[nas-tee] / ˈnæs ti /

adjective

nastier, nastiest

1. physically filthy; disgustingly unclean.

   a nasty pigsty of a room.

   Synonyms:

   grimy, foul, dirty

   Antonyms:

   unstained, spotless, immaculate, clean

2. offensive to taste or smell; nauseating.

   This ointment is really nasty—couldn't they make it smell less vile?

   Synonyms:

   ugly, catty, bitchy, malevolent, malicious, mean, repellent, repulsive, sickening

3. offensive; objectionable.

   a nasty habit.

4. vicious, spiteful, or unkind.

   a nasty dog;

   a nasty rumor.

5. bad or hard to deal with, encounter, undergo, etc.; dangerous; serious: a nasty accident.

   a nasty cut;

   a nasty accident.

6. very unpleasant or disagreeable.

   nasty weather.

   Synonyms:

   inclement, stormy

7. morally filthy; obscene; indecent.

   a nasty word.

   Synonyms:

   smutty

8. Slang. formidable: a young pitcher with a nasty slider.

   the raw, nasty power of this engine;

   a young pitcher with a nasty slider.

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noun

plural

nasties

1. Informal. a nasty person or thing.

-nasty ² American  

1. a combining form with the meaning “nastic pressure,” of the kind or in the direction specified by the initial element.

   hyponasty.

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nasty ¹ British  

/ ˈnɑːstɪ /

adjective

1. unpleasant, offensive, or repugnant

2. (of an experience, condition, etc) unpleasant, dangerous, or painful

   a nasty wound

3. spiteful, abusive, or ill-natured

4. obscene or indecent

5. informal a cruel or mean person

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noun

1. an offensive or unpleasant person or thing

   a video nasty

-nasty ² British  

combining form

1. indicating a nastic movement to a certain stimulus

   nyctinasty

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Other Word Forms

• -nastic combining form
• nastily adverb
• nastiness noun

Etymology

Origin of nasty¹

First recorded in 1350–1400; Middle English, further origin unknown

Origin of -nasty²

< Greek nast ( ós ) pressed close ( nastic ) + -y ³

Explanation

Something nasty is filthy, foul, dirty, or awful. Nasty isn't a word for anything nice. The main meaning of nasty is for things that are unpleasant and very gross. If someone throws up in class, at least one student will probably say, "That's nasty!" The smell of a bathroom is nasty. A song full of dirty words is nasty in a different way. Nasty can also mean "extremely." In football, a vicious hit can be called a nasty hit. A mean person is a nasty person too.

Example Sentences

Still, demand for golden AI shares is so strong that outside a nasty recession, the possible $1 trillion IPOs of OpenAI, Anthropic and SpaceX should proceed.

From The Wall Street Journal • Apr. 12, 2026

They could see the ways girls were performing a strange kind of female role in order to please boys who are themselves performing a nasty version of masculinity.

From BBC • Apr. 12, 2026

That segment of the show largely stripped out the guitars to focus on clubby techno and nasty slashes of synth noise.

From Los Angeles Times • Apr. 12, 2026

Micron, a recent darling of the semiconductor industry, is now on a nasty six-day losing streak, which has erased about one-quarter of its value.

From Barron's • Mar. 26, 2026

They were dressed like gentiles, and most wore no hats, as though to spite the nasty weather and spit in the face of tradition.

From "The City Beautiful" by Aden Polydoros

Related Words

• awful
• dirty
• fierce
• horrible
• icky
• murderous
• noxious
• obnoxious
• ornery
• outrageous
• rough
• tough
• unpleasant
• vile
• vulgar