Musca Syllabification: (Mus·ca)Pronunciation: /ˈməskə/ AstronomyDefinition of Musca a small southern constellation (the Fly), lying in the Milky Way between the Southern Cross and the south celestial pole. (as genitive Muscae /ˈməskē/) used with a preceding letter or numeral to designate a star in this constellation:the star Beta MuscaeOrigin:LatinMusca in other Oxford dictionaries Definition of Musca in the British & World English dictionary