fun

American  

[fuhn] / fʌn /

noun

1. something that provides mirth or amusement.

   A picnic would be fun.

   Synonyms:

   gaiety, play, pleasure, merriment

2. enjoyment or playfulness.

   She's full of fun.

   Synonyms:

   gaiety, play, pleasure, merriment

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verb (used with or without object)

funned, funning

1. Informal. joke; kid.

adjective

funner, funnest

1. Informal. of or relating to fun, especially to social fun.

   a fun thing to do; really a fun person; the funnest game.

2. Informal. whimsical; flamboyant.

   The fashions this year are definitely on the fun side.

idioms

1. for / in fun, as a joke; not seriously; playfully.

   His insults were only in fun.

2. make fun of, to make the object of ridicule; deride.

   The youngsters made fun of their teacher.

3. like fun, certainly not; of doubtful truth.

   He told us that he finished the exam in an hour. Like fun he did!

fun British  

/ fʌn /

noun

1. a source of enjoyment, amusement, diversion, etc

2. pleasure, gaiety, or merriment

3. jest or sport (esp in the phrases in or for fun )

4. facetious amusement; frivolous activity

5. informal

   1. (adverb) quickly; vigorously

   2. (interjection) not at all! certainly not!

6. to ridicule or deride

7. (modifier) full of amusement, diversion, gaiety, etc

   a fun sport

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verb

1. informal (intr) to act in a joking or sporting manner

fun More Idioms  

More idioms and phrases containing fun

• for fun
• funny
• like fun
• make fun of
• more fun than a barrel of monkeys

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Etymology

Origin of fun

First recorded in 1675–85; dialectal variant of obsolete fon “to befool”; fond ¹ ( def. )

Explanation

When you are having fun, you are having a good time. Watching little kids jump around inside an inflatable bouncy house, you can instantly tell how much fun they're having. There is no mistaking fun when you're having it, and it's generally used to mean exactly what it sounds like, some activity or experience that's purely enjoyable. When fun takes the form of an adjective, it's informal, not strictly grammatically correct. So while you can say, "Being with her is so much fun," you can't correctly say, "She is such a fun girl." Fun turns a little bit mean when you're making fun of, or teasing, your friend. In this case, it might be fun for you, but it's probably not very much fun for him.

Example Sentences

Getting to “go on the computer” was an opportunity for entertainment, yes, but it was also a chance to learn in a fun, controlled environment.

From Salon • Apr. 12, 2026

And when does poking fun at arrested manhood cross into enabling it?

From The Wall Street Journal • Apr. 12, 2026

“It was fun while it lasted,” she told me.

From Slate • Apr. 12, 2026

But at that time - I think that's the fun thing about when you're young - you just go out and play.

From BBC • Apr. 11, 2026

At least no one else had been on the bus to hear the driver making fun of them.

From "Found" by Margaret Peterson Haddix

Related Words

• celebration
• distraction
• enjoyment
• joke
• joy
• laughter
• pastime
• pleasure
• sport