Maqsurah (Arabic مقصورة) (literally "closed-off space"), an enclosure, a box or wooden screen near the mihrab or the center of the qibla wall, which was originally designed to shield a worshipping ruler from assassins. The imam officiating inside the maqsurah typically belonged to the same school of law to which the ruler belonged.
There also may have been some spiritual connotation similar to the chancel screen in churches. They were often wooden screens decorated with carvings or interlocking turned pieces of wood (similar to a mashrabiya).
Historically, it was first used by the Umayyad caliphMuawiyah I in the Umayyad Mosque of Damascus, where the so-called "Mihrab of the Companions (of the Prophet)" belonged to the "Maqsura of the Companions".