Rome-runner
/ˈrəʊmˌrʌnə/Chiefly depreciative. Now historical
noun
A person who travels to Rome with the aim of securing a benefice, ecclesiastical privilege, etc. Formerly also: †a person who carries out papal instructions, an agent of the Pope (obsolete ).
Origin
Late Middle English; earliest use found in William Langland (c1325–c1390), poet. From Rome + runner.