Game concept
Execute
The game also links it as Execution, Executions, Executed, Executing.
From the game's encyclopedia
Imprisoned Characters can be Executed. This is considered Tyrannical unless their imprisoner has an Execution Reason.
Executions increase your Dread and are never well received by the Close Family of the unfortunate target.
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.
Execute is an entry of Crusader Kings III's in-game encyclopedia. The game explains it: "Imprisoned Characters can be Executed." The game also links it as Execution, Executions, Executed and Executing. 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.