MAINPERN'OR, noun In law, a surety for a prisoner's appearance in court at a day. Mainpernors differ from bail, in that a man's bail may imprison or surrender him before the stipulated day of appearance; mainpernors can do neither; they are bound to produce him to answer all charges whatsoever.
Source: Webster's 1828 American Dictionary ↗ · public-domain · returned verbatim, no AI