hy·o·glos·sus 
(hī′ō-glŏsəs)
(hī′ō-glŏsəs)n. pl. hy·o·glos·si (-glŏsī′)
A muscle whose action retracts and pulls down the side of the tongue.
[New Latin hȳoglossus : hȳoīdēs, the hyoid bone (from which its lower end arises); see HYOID + Greek glōssa, tongue.]