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curve ball

1. In baseball, a ball that curves in its trajectory toward home plate. He's a good batter, but he has a hard time hitting a curve ball.
2. An unexpected occurrence or thing that causes confusion or uncertainty. I thought I had confirmed my hypothesis, so these results are a real curve ball.
3. A deceptive action or thing. I don't know, I think her sudden displays of affection are just a curve ball to get me to trust her.
See also: ball, curve

throw (one) a curveball

To introduce a problem piece of information that shocks, bewilders, or confounds one or makes it more difficult for one to succeed. An allusion to baseball, in which a curveball is a pitch that arcs toward the batter in order to be more difficult to hit. Primarily heard in US. The end of that trick always throws the audience a curveball. I love watching their faces as they desperately try to figure it out. It really threw Stu a curveball when Olivia announced she was leaving the company.
See also: curveball, throw

throw somebody a ˈcurveball

(American English) surprise somebody with a problem, situation, question, etc. that they do not expect and which is difficult to deal with: Just when you think you have it all under control, life throws you a curve ball.
In baseball, a curveball is a ball that is difficult to hit because it does not move in a straight line.
References in periodicals archive ?
In March, for instance, airports region-wide were thrown a curveball by the abrupt imposition of the laptop ban on flights to the US.
The White House did not interview Curveball because they knew his account of Saddam's WMD programme was made up.
We've all had our share of curveballs even if we've never held a Louisville Slugger: unexpected events and issues that we have to deal with, generally something of an unpleasant nature.
Most pitchers usually rely on curveballs or fastballs to strike out their opponents.
Precession could affect curveball quality by continuously shifting the angle of the spin axis during the bali's trajectory, thereby continuously redirecting instantaneous deflection and reducing total effective deflection.
Powell's speech to the United Nations on February 5, 2003, had cited intelligence about Saddam' bio-weapons programme gained from a defector codenamed Curveball.
Ahmed Hassan Mohammed was the false name on the passport Curveball used to fly to Munich in 1999 and apply for asylum.
Halliday) had an unbelievable curveball today," Croteau said.
As Chart 2 shows, the chart consists of 40 rectangular strike zones marked fastball or curveball.
Curveball, you will recall, was the CIA's source for the fiction about Iraq's mobile biological weapons laboratories that the Bush admin peddled to justify the war.
Then came another curveball in 1992: She developed cancer.