Game concept
Oath
The game also links it as Oaths.
From the game's encyclopedia
Oaths are sworn during the Coronation Activity by the Host, and play an important role in securing the Legitimacy of a new Ruler as they step up to take the throne.
Oaths will unlock special time-limited Decisions which the ruler will have to complete to prove themselves worthy of their Title. The rewards gained will be affected by the Magnificence of the coronation.
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.
Oath is an entry of Crusader Kings III's in-game encyclopedia. The game explains it: "Oaths are sworn during the Coronation Activity by the Host, and play an important role in securing the Legitimacy of a new Ruler as they step up to take the throne." It is part of Coronation. The game also links it as Oaths. Patch 1.20.1.2, from game/common/game_concepts/ach_game_concepts.txt and game/localization/english/game_concepts_l_english.yml.
Source: game/common/game_concepts/ach_game_concepts.txt, game/localization/english/game_concepts_l_english.yml and the English localisation, Crusader Kings III 1.20.1.2.