Game concept
Clan House Head
The game also links it as Clan House Heads, Head.
From the game's encyclopedia
A Clan House Head is in many ways like a normal House Head, but differs in some notable ways.
Clan House Heads do not get a Weak Hook on all the members of their House. They have more influence over House Unity than other house members. Additionally, any house member may challenge a Clan House Head for superiority to become the House Head themself.
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.
Clan House Head is an entry of Crusader Kings III's in-game encyclopedia. The game explains it: "A Clan House Head is in many ways like a normal House Head, but differs in some notable ways." It is part of House Head. The game also links it as Clan House Heads and Head. 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.