Game concept
Economic Building
The game also links it as Economic Buildings.
From the game's encyclopedia
Economic Buildings are Buildings whose primary function is to increase their holding's Domain Income.
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.
Economic Building is an entry of Crusader Kings III's in-game encyclopedia. The game explains it: "Economic Buildings are Buildings whose primary function is to increase their holding's Domain Income." It is part of Building. The game also links it as Economic Buildings. 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.