WRIT OF MAINPRIZE, English law. A writ directed to the sheriff (either
generally, when any man is imprisoned for a bailable offence, and bail has
been refused; or specially, when the offence or cause of commitment is not
properly bailable below) commanding him to take sureties for the prisoner's
appearance, commonly called mainpernors, and to set him at large. 3 B]. Com.
128. Vide Mainprize.