Game concept
Dynasty Head Interaction
The game also links it as Dynasty Head Interactions.
From the game's encyclopedia
Interactions that are uniquely available to the Dynasty Head of a Dynasty, against other members of that dynasty.
They cost Renown to use.
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.
Dynasty Head Interaction is an entry of Crusader Kings III's in-game encyclopedia. The game explains it: "Interactions that are uniquely available to the Dynasty Head of a Dynasty, against other members of that dynasty." It is part of Dynasty Head. The game also links it as Dynasty Head Interactions. 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.