Noah Webster
Mainprize
MA'INPRIZE, noun
1. In law, a writ directed to the sheriff, commanding him to take sureties for the prisoner's appearance, and to let him go at large. These sureties are called mainpernors.
2. Deliverance of a prisoner on security for his appearance at a day.
MA'INPRIZE, verb transitive To suffer a prisoner to go at large, on his finding sureties, mainpernors, for his appearance at a day.