Definition
A knave is an archaic term for a dishonest or unscrupulous person, often a male. Think of it as an old-fashioned word for a sneaky cheat or a rascal. Unlike a simple mistake, a knave's actions are intentionally deceitful. It implies a lack of morals and trustworthiness. The term often appears in older literature and fairy tales. Calling someone a knave is a serious insult.