In Egyptian architecture, a chamber found in some mastabas of the Old Kingdom (2686-2181 BC), appearing during the reign of Djoser and widespread in the Giza and Saqqara cemeteries after Menkaure's reign. It consists of a walled-up chamber provided in a mortuary chapel or burial shaft to contain an image or statue of the deceased. Statues of the ka of the deceased were usually placed here. It derives from the Arabic word for 'cellar'.