Writ of Mainprize Law and Legal Definition

Writ of Mainprize is an English writ directed to the sheriff commanding him to take sureties for the prisoner's appearance, and to set him at large. The writ can be issued either generally or specifically. It is issued generally, when a man is imprisoned for a bailable offense, and bail has been refused. It is issued specially, when the offense or cause of commitment is not properly bailable.