to have a specialinterest or reason for being involved in something; a personal interest in something; an ulterior motive. This expression comes from a story entitled "Who'll Turn the Grindstone?" first published in 1811. In the story, a man with a dullax tricks a young boy. By flattering the boy's good looks and intelligence, the man gets him to sharpen the ax on his father's grindstone. Once the ax is sharpened the man rudely sends the boy off with no thanks or recompense. The author closes his tale with the comment, "When I see a merchant overpolite to his customers, begging them to taste a little brandy and throwing half his goods on the counter-thinks I, that man has an ax to grind."