genioglossus
noun
ge·nio·glos·sus
| \ -ˈgläs-əs
, -ˈglȯs-
\
, -ˈglȯs-
\
plural genioglossi\ -ˌī
\
\
Medical Definition of genioglossus
: a fan-shaped muscle that arises from the superior mental spine, inserts on the hyoid bone and into the tongue, and serves to advance and retract and also to depress the tongue