isabel. In North America it is also called a one-room apartment. It consists of one large room which serves as the living, dining, and bedroom. Kitchen facilities may be located in the central room, and the bathroom is often in its own smaller room. A large one-room apartment is sometimes called a studio, and a smaller version is called an efficiency apartment or a bachelor apartment. If the living space shares a bathroom or kitchen, then it is referred to as a 'room'.

One more variation: one-bedroom apartment

one room apartment

A small apartment with one room - bachelor apartment. A large apartment with one room - studio apartment.

Variation: one-roomed flat