We found 22 dictionaries that define the word optical illusion:

General (18 matching dictionaries)

1. optical illusion: Longman Dictionary of Contemporary English
2. optical illusion: Merriam-Webster
3. optical illusion: Oxford Learner's Dictionaries
4. optical illusion: American Heritage Dictionary of the English Language
5. optical illusion: Collins English Dictionary
6. optical illusion: Vocabulary.com
7. optical-illusion: Wordnik
8. optical illusion: Cambridge Advanced Learner's Dictionary
9. optical illusion: Wiktionary
10. optical illusion: Dictionary.com
11. Optical Illusion (Time Requiem album), Optical Illusion (album), Optical illusion: Wikipedia, the Free Encyclopedia
12. optical illusion: Rhymezone
13. optical illusion: AllWords.com Multi-Lingual Dictionary
14. optical illusion: FreeDictionary.org
15. optical illusion: Mnemonic Dictionary
16. optical illusion: TheFreeDictionary.com

Art (1 matching dictionary)

17. optical illusion: ArtLex Lexicon of Visual Art Terminology

Medicine (1 matching dictionary)

18. optical illusion: Merriam-Webster Medical Dictionary

Science (2 matching dictionaries)

19. A Glossary of Mathematical Terms (No longer online)
20. Optical Illusion: Eric Weisstein's World of Mathematics

(Note: See optical_illusions as well.)

Definitions from Wiktionary (optical illusion) ▸ noun:  An image that is visually deceptive or misleading. Similar: fallacy, misleading, trompe-d'œil, trompe d'œil, illusion, tromp-l'oeil, misappearance, misfigure, deception, false light, more... Opposite: reality, truth, actuality Types: Ames room, café wall illusion, moon illusion, Ponzo illusion, Zöllner illusion, J, more... Adjectives: monographic, fringing, relief, half-length, black-and-white, chiaroscuro, coroplastic, photogenic, full-length, sculptural, sculpted ▸ Words similar to optical illusion ▸ Usage examples for optical illusion ▸ Idioms related to optical illusion ▸ Wikipedia articles (New!) ▸ Words that often appear near optical illusion ▸ Rhymes of optical illusion ▸ Invented words related to optical illusion