ge·ni·o·glos·sus 
(jē′nē-ō-glŏsəs)
(jē′nē-ō-glŏsəs)n. pl. ge·ni·o·glos·si (-ī′)
Either of a pair of muscles that connect the jaw and tongue and that depress and protrude the tongue.
[New Latin genioglōssus : Greek geneion, chin; see GENIAL2 + Greek glōssa, tongue.]