mainpernorEtymologyFrom Middle English meynpernour, from Anglo-Norman mainprenour, from mainprendre + -our. See modern French main, preneur.mainpernor means in England in the Middle Ages, a surety (kind of guarantor); a guarantor that a ship would dock. Lexicurio rates it Sui generis — a strength score of 88 out of 100.nounIn England in the Middle Ages, a surety (kind of guarantor); a guarantor that a ship would dockIn England in the Middle Ages, a surety (kind of guarantor); under the old writ of mainprise, a guarantor for a prisoner's appearance in court.