Game concept
Nominate
The game also links it as Nomination, Nominations, Nominate Heir.
From the game's encyclopedia
Under Elective Succession Laws, each Elector can Nominate their preferred Title Heir. Valid candidates and Elector voting preferences differ depending on the specific Law.
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.
Nominate is an entry of Crusader Kings III's in-game encyclopedia. The game explains it: "Under Elective Succession Laws, each Elector can Nominate their preferred Title Heir." The game also links it as Nomination, Nominations and Nominate Heir. 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.