In the medieval period the room would simply have been referred to as the hall unless the building also had a secondary hall, but the term great hall has been predominant for surviving rooms of this type for several centuries to distinguish them from the different type of hall found in post-medieval houses.

A room in a castle is rarely just called a "room"; names are traditionally dictated by the room's specific function and status. The most important communal space is the Great Hall, used for feasting and administrative business. Sleeping quarters for the lord and lady were known as the Solar, a more private and comfortable chamber often located on an upper floor. Guests might stay in the Presence Chamber, while the Great Chamber served as a formal reception room. Defensive or storage spaces include the Keep (the central stronghold), the Donjon, and the Undercroft (a vaulted basement for storage). Religious needs were met in the Chapel. For more "unpleasant" necessities, castles featured a Garderobe, which was a primitive latrine built into the castle walls. Service areas included the Buttery (for storing ale/wine), the Pantry (for bread), and the Scullery. In 2026, many of these architectural terms are preserved in heritage sites, giving visitors a glimpse into the highly stratified and functional nature of medieval domestic life.