Any of various stout,two-winged flies,chiefly of the genera Gasterophilus and Oestrus,having larvae that are parasitic on various animals,especially horses and sheep,and sometimes on humans.

• 马蝇，一种胃蝇属和狂蝇属身体大的双翼蝇，其幼虫寄生于多种动物，尤其是马和羊，有时也寄生在人体内。