Game concept
Archbishop
The game also links it as Archbishops, Archbishop's, Archbishops'.
From the game's encyclopedia
An Archbishop is the Christian holder of an Archdiocese, a duchy-tier Clerical Title whose Clerical Region may span several Realms.
As the Religious Superior of the Bishops and lesser Clergy within that region, an Archbishop ranks above an ordinary Bishop and answers in turn to the Head of Faith.
The game's text for patch 1.20.1.2. Words in blue are entries of the encyclopedia: hover one to read it, as in the game.
Archbishop is an entry of Crusader Kings III's in-game encyclopedia. The game explains it: "An Archbishop is the Christian holder of an Archdiocese, a duchy-tier Clerical Title whose Clerical Region may span several Realms." It is part of Faith. The game also links it as Archbishops, Archbishop's and Archbishops'. Patch 1.20.1.2, from game/common/game_concepts/pam_game_concepts.txt and game/localization/english/game_concepts_l_english.yml.
Source: game/common/game_concepts/pam_game_concepts.txt, game/localization/english/game_concepts_l_english.yml and the English localisation, Crusader Kings III 1.20.1.2.