mainprise

Etymology
From, , from.

Noun

 * 1)  A writ directed to the sheriff, commanding him to take sureties, called mainpernors, for the prisoner's appearance, and to let him go at large.
 * 2)  Deliverance of a prisoner on security for his appearance at a day.

Verb

 * 1)  To allow (a prisoner) to go at large, on his finding sureties, or mainpernors, for his appearance on a given day.