crystal ball

1. A glass or crystal orb used by fortune-tellers and mystics in popular culture to see into the future. The soothsayer, peering into her crystal ball, foretold that I would come to possess a great fortune by the year's end. Even if a fortune-teller gazed into her crystal ball, I don't think I would believe the predictions she gave me. It was so eerie—all of the color drained from the mystic's face as soon as she looked into her crystal ball.

2. By extension, any figurative means of predicting future events. She must have some kind of crystal ball for the economy, because every business decision she's made has been timed perfectly to market fluctuations. Well, Mike, what does your crystal ball say about the team's chances in the playoffs? The renowned analyst is predicting a massive economic downturn. She must be gazing into her crystal ball or something.

a crystal ball

COMMON You talk about a crystal ball when you are saying how difficult it is to predict the future. What you really need to help you select your new car is a crystal ball to tell you how much it will be worth in three or four years' time. Note: You can call the activity of predicting the future crystal ball gazing. Can I ask you now to do a bit of crystal ball gazing? How high do you think the price of oil could go? Note: A crystal ball is a glass ball used by some traditional fortune-tellers (= people who predict what will happen to you in the future). They say that they can see visions of future events within the ball.