Game concept
Elector
The game also links it as Electors, Election, Elections.
From the game's encyclopedia
Electors are the characters who get to vote on their preferred Title Heir under Elective Succession Laws. The specific Law determines who is considered an Elector.
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.
Elector is an entry of Crusader Kings III's in-game encyclopedia. The game explains it: "Electors are the characters who get to vote on their preferred Title Heir under Elective Succession Laws." It covers Prince-Elector. The game also links it as Electors, Election and Elections. 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.