A drawing room is a room in a house where visitors may be entertained. The name is derived from the sixteenth-century terms "withdrawing room" and "withdrawing chamber," which remained in use through the seventeenth century, and made its first written appearance in 1642 (OED). In a large sixteenth- to early eighteenth-century English house, a withdrawing room was a room to which the owner of the house, his wife, or a distinguished guest who was occupying one of the main apartments in the house could "withdraw" for more privacy. It was often off the great chamber (or the great chamber's descendant, the state room or salon) and usually led to a formal, or "state" bedroom.
In eighteenth-century London, the royal morning receptions that the French called leves were called "drawing rooms", with the sense originally that the privileged members of court would gather in the drawing room outside the king's bedroom, where he would make his first formal public appearance of the day.
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It is actually the Withdrawing Room - the room where you go to after you leave the Dining Room, it is a room where you relax, read, listen to music or sit and talk with visitors etc. Also called the Sitting Room or more commonly the Lounge. The Hall is the small area where you enter the house, the Withdrawing Room Dining Room, Kitchen etc. all lead off the Hall/Hallway.