Rules as Written (terminology)
From D&D Wiki
Rules as written in the D&D game refers to the rules that WoTC publishes. In a wider sense it means the rules of the game being played. Rules as written is used to distinguish these from both house rules and what may have been intended that the rules were to be, such as a reference in a blurb to an ability that the class in question does not actually get or that is being used incorrectly. It is important to note that often the rules as written are open to interpretation as there may be multiple viewpoints on what the RAW is.