optical illusion optical glass • optical instrument · · · Info · Definitions · Characters · · optical illusion · · Text Common · · Latin · · Scripts 16 · · Length 6 · · Syllables Definitions · · · (noun) an optical phenomenon that results in a false or deceptive visual impression. Synonyms: optical illusion. · · Noun Definition 1 Characters · · space U+0020 a latin small letter a U+0061 c latin small letter c U+0063 i latin small letter i U+0069 l latin small letter l U+006C n latin small letter n U+006E o latin small letter o U+006F p latin small letter p U+0070 s latin small letter s U+0073 t latin small letter t U+0074 u latin small letter u U+0075