in·ter·nun·ci·o 
(ĭn′tər-nŭnsē-ō′, -nn-)
(ĭn′tər-nŭnsē-ō′, -nn-)n. pl. in·ter·nun·ci·os
A Vatican diplomatic envoy or representative ranking just beneath a nuncio. No longer in use.
[Italian internunzio, from Latin internūntius, mediator : inter-, inter- + nūntius, messenger; see NUNCIO.]