To maintain some form of relationship with someone without revealing one's true feelings or intentions; to keep someone in an uncertain position. If you don't want to marry him, then you have to tell him that—you can't keep him dangling any longer! A: "I'm never going to get a promotion, am I?" B: "With the way the boss keeps you dangling, I doubt it."

To hang loosely from something, as if likely to fall. Can you secure that picture before it falls? It's just dangling from the nail.