Game concept
Temple Holding
The game also links it as Temple, Temples, Temple Holdings.
From the game's encyclopedia
Temples are a Holding Type that can be held by members of the Clergy as Church Holdings (the Theocratic Government Form). However, in Faiths with the Lay Clergy Doctrine, anyone can hold Temples without penalty.
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.
Temple Holding is an entry of Crusader Kings III's in-game encyclopedia. The game explains it: "Temples are a Holding Type that can be held by members of the Clergy as Church Holdings (the Theocratic Government Form)." It is part of Holding Type. The game also links it as Temple, Temples and Temple Holdings. Patch 1.20.1.2, from game/common/game_concepts/00_game_concepts.txt and game/localization/english/game_concepts_l_english.yml.
Source: game/common/game_concepts/00_game_concepts.txt, game/localization/english/game_concepts_l_english.yml and the English localisation, Crusader Kings III 1.20.1.2.