Cubiculum
A cubiculum was a private room in a domus, an ancient Roman house occupied by a high-status family. It usually led directly from the atrium, but in later periods it was sometimes adjacent to the peristyle. It was used for the functions of a modern bedroom, sleep and sex, as well as for business meetings, the reception of important guests and the display of the most highly-prized works of art in the house. The cubiculum was used for quiet or secret meetings and could have been used as a library. It was also a preferred venue for murder and suicide. A room used only for sleeping was not classed as a cubiculum.
The private nature of the cubiculum made it a place for contemplation and religious observance, especially when illicit. According to the Actus Silvestri, Constantine the Great first learned of Christianity in his cubiculum and fasted there for a week before his first confession and baptism.
