noun
1. A complex riddle or puzzle.
example
2. Indeed, Michael Weatherly, who plays Agent Tony DiNozzo, says the "brain-teaser, easter-egg-y... fabricated realities" will bring back characters who have long been dead.
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3. Last summer's hit "life is but a dream" brain-teaser arrives on pay cable, a perfect opportunity to kick back and try to figure out what's what and what's real all over again.
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4. The rise of ninjas in the tech world is being fueled in part by Amazon. com Inc., the e-commerce giant, which hosts a ninja brain-teaser contest at job fairs and industry events when hiring computer-software writers.
