muscae volitantesPronunciation: /ˌmʌsiː ˌvɒlɪˈtantiːz/Definition of muscae volitantes noun Medicine dark specks appearing to float before the eyes, generally caused by particles in the vitreous humour of the eye. Origin: mid 18th century: Latin, literally 'flying flies'muscae volitantes in other Oxford dictionaries Definition of muscae volitantes in the US English dictionary