in the Roman Catholic Church, a cleric sent on a mission, ecclesiastical or diplomatic, by the pope as his personal representative. Three types of legates are recognized by canon law. A legatus a latere (a legate sent from the pope's side, as it were) is a cardinal who represents the pope on some special assignment with such powers as are delegated to him. Nuncios (nuncio), pronuncios, and internuncios are sent to countries that have diplomatic relations with the Holy See; they promote friendly relations and observe and report to the pope on the state of the church in that region. Apostolic delegates (apostolic delegate) are prelates who are appointed by the pope as his representatives to the church of a region. They channel information between the local ecclesiastical hierarchy and the Holy See.

official who acted as a deputy general to governors of provinces conquered by ancient Rome in the 2nd and 1st centuries BC, during the period of the republic. In the latter part of the 1st century BC, Julius Caesar initiated the practice of appointing legates to command legions in the army. This practice became customary under the emperor Augustus (27 BC–AD 14). Under the early empire, in the 1st and 2nd centuries AD, a province containing one or more legions was governed by a military commander with the title legatus Augusti pro praetore (propraetorian legate of the emperor).