hypoglossal nervePronunciation: /ˌhʌɪpə(ʊ)ˈglɒs(ə)l/Definition of hypoglossal nerve noun Anatomy each of the twelfth pair of cranial nerves, supplying the muscles of the tongue. Origin: mid 19th century: hypoglossal from hypo- 'under' + Greek glōssa 'tongue' + -alhypoglossal nerve in other Oxford dictionaries Definition of hypoglossal nerve in the US English dictionary