By/with your leave Definition 1 of 2Pro Tip 1/3Polite Permission The phrase is a very formal way to ask for approval before you do something. By your leave, sir, I would like to close the shop early today. Pro Tip 2/3Old-fashioned It's an archaic phrase, so use it to sound quaint or in historical settings. With your leave, madam, I shall retrieve your carriage. Pro Tip 3/3Literary Usage You may find it used in literature to convey historical or formal settings. By your leave, I will speak to your father about our engagement.