fantasy

UK: /ˈfæntəsi/ US: /ˈfæntəsi, -zi/ ,(fan′tə sē, -zē)

Inflections of 'fantasy' (n): npl: fantasies

Inflections of 'fantasy' (v): (⇒ conjugate)

fantasies

v 3rd person singular

fantasying

v pres p

fantasied

v past

fantasied

v past p

WordReference Random House Learner's Dictionary of American English © 2026

fan•ta•sy /ˈfæntəsi, -zi/   n., pl. -sies. 

1. imagination, esp. when it is let free and not held back:
   [uncountable] indulging in fantasy from time to time.
2. Psychology the succession of mental images formed in this way:
   [countable] He had this fantasy about the tenant across the hall.
3. a belief or notion based on no solid foundation;
   illusion:
   [countable] She had a fantasy that he was trying to poison her.

WordReference Random House Unabridged Dictionary of American English © 2026

fan•ta•sy  (fan′tə sē, -zē), n., pl. -sies, v., -sied, -sy•ing. 
n. 

1. imagination, esp. when extravagant and unrestrained.
2. the forming of mental images, esp. wondrous or strange fancies;
   imaginative conceptualizing.
3. a mental image, esp. when unreal or fantastic;
   vision:
   a nightmare fantasy.
4. Psychology an imagined or conjured up sequence fulfilling a psychological need;
   daydream.
5. a hallucination.
6. a supposition based on no solid foundation;
   visionary idea;
   illusion:
   dreams of Utopias and similar fantasies.
7. caprice;
   whim.
8. an ingenious or fanciful thought, design, or invention.
9. Literature Also, fantasia. an imaginative or fanciful work, esp. one dealing with supernatural or unnatural events or characters:
   The stories of Poe are fantasies of horror.
10. Music and Dance fantasia (def. 1).

v.t., v.i. 

11. to form mental images;
    imagine;
    fantasize.
12. Slang Terms [Rare.] to write or play fantasias.

Also, phantasy. 

• Greek phantasía an idea, notion, image, literally, a making visible; see fantastic, -y³
• Latin phantasia
• Anglo-French, Old French)
• Middle English fantasie imaginative faculty, mental image (1275–1325

Synonyms

• 1. See fancy. 

Collins Concise English Dictionary © HarperCollins Publishers::

fantasy, phantasy / ˈfæntəsɪ/ noun ( -sies)

1. imagination unrestricted by reality
2. (as modifier): a fantasy world
3. a creation of the imagination, esp a weird or bizarre one
4. a series of pleasing mental images, usually serving to fulfil a need not gratified in reality
5. a whimsical or far-fetched notion
6. an illusion, hallucination, or phantom
7. a highly elaborate imaginative design or creation
8. another word for fantasia, fancy13, (rarely) development5
9. literature having a large fantasy content
10. (modifier) of or relating to a competition, often in a newspaper, in which a participant selects players for an imaginary ideal team, and points are awarded according to the actual performances of the chosen players: fantasy football

verb ( -sies, -sying, -sied)

1. a less common word for fantasize

Etymology: 14th Century fantasie, from Latin phantasia, from Greek phantazein to make visible