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Synonyms

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

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
"Collins English Dictionary — Complete & Unabridged" 2012 Digital Edition © William Collins Sons & Co. Ltd. 1979, 1986 © HarperCollins Publishers 1998, 2000, 2003, 2005, 2006, 2007, 2009, 2012

verb

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

"Collins English Dictionary — Complete & Unabridged" 2012 Digital Edition © William Collins Sons & Co. Ltd. 1979, 1986 © HarperCollins Publishers 1998, 2000, 2003, 2005, 2006, 2007, 2009, 2012
fun More Idioms  

    More idioms and phrases containing fun

Etymology

Origin of fun

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

Example Sentences

Examples are provided to illustrate real-world usage of words in context. Any opinions expressed do not reflect the views of Dictionary.com.

“For the coffee-lover, the intricate ritual of coffee preparation adds fun and pleasure to life,” he argues.

From Slate • Apr. 4, 2026

"It's really fun to be floating around" in zero gravity, he added.

From Barron's • Apr. 3, 2026

Along with making fun, relatable music, Cissé deals with the huge undertaking of building a successful pop identity as a Black girl in a white-girl-dominated realm.

From Los Angeles Times • Apr. 3, 2026

"I talked to a lot of people and had quite a bit of fun."

From BBC • Apr. 2, 2026

A favorite Broadway actress sang “The Rochester Knockings at Barnum’s Hotel,” and Mysterious Knockings, “a new farce full of glorious fun and frolic,” played at a popular theater.

From "American Spirits" by Barb Rosenstock

Definitions and idiom definitions from Dictionary.com Unabridged, based on the Random House Unabridged Dictionary, © Random House, Inc. 2023

Idioms from The American Heritage® Idioms Dictionary copyright © 2002, 2001, 1995 by Houghton Mifflin Harcourt Publishing Company. Published by Houghton Mifflin Harcourt Publishing Company.