fan·ta·sy (fanÆtà s", -z"), 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. Psychol. 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. Also, fantasia. Literature. 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. fantasia (def. 1).
–v.t., v.i.
11. to form mental images; imagine; fantasize.
12. Rare. to write or play fantasias.
Also, phantasy.
[1275–1325; ME fantasie imaginative faculty, mental image (< AF, OF) < L phantasia < Gk phantas#a an idea, notion, image, lit., a making visible; see FANTASTIC, -Y3]