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

Example Sentences

She’s a 16-year-old Labrador retriever who became the target of a nasty custody fight between a California couple after the dissolution of their domestic partnership.

From Los Angeles Times • Mar. 27, 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

In August 2024, media executive Jeff Shell made his way to his lawyer’s office in the Los Angeles neighborhood of Century City to meet someone he had been told was behind nasty rumors about him.

From The Wall Street Journal • Mar. 20, 2026

There is something "particularly nasty about this disease", which causes "untold pain" to families, Nutt said.

From BBC • Mar. 17, 2026

Clare shot a nasty look at the sky all around, hoping the Afterlife got the message.

From "The Undead Fox of Deadwood Forest" by Aubrey Hartman

Related Words

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