Banquo is a character in Shakespeare’s play Macbeth. He is a Scottish lord and, at the start, a friend of Macbeth. Witches tell him that his children will be kings, though he himself will not. That promise frightens Macbeth, who later gives secret orders for Banquo to be murdered. Banquo’s son Fleance gets away. Later, at a feast, Banquo comes back as a ghost. Only Macbeth can see him. The ghost sits in Macbeth’s place and will not let him enjoy the celebration. It is there to press on him: you are guilty, and this plan will not hold. Teachers sometimes say “Banquo’s ghost” when they mean a bad memory that will not sit down and be quiet — that stretch comes from this scene. You say it BAN-kwo (like “quote” without the t). It is this man’s name, not a common English word for a type of person. Where the name first came from is uncertain, so we should not pretend we know a tidy origin story.

班柯（莎士比亞《馬克白》中的角色）