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1. A phrase used to literally start a game. Is everyone lined up? OK, game on!
2. A phrase used when one is ready to meet or pursue a particular challenge. All right, game on—let's get the cleaning started!
3. A phrase used when one is eager to benefit from a particular situation. I thought I was doing the work for free, but hey, if she wants to pay me, game on!
Farlex Dictionary of Idioms. © 2015 Farlex, Inc, all rights reserved.
People say game on to mean that they are ready for something challenging to begin. You think you can beat me? Game on! Note: You can also say it's game on for someone to mean that they are about to face a challenge. It's game on for toy makers as Christmas approaches.
Collins COBUILD Idioms Dictionary, 3rd ed. © HarperCollins Publishers 2012
game on1 a signal for play to begin in a game or match. 2 said when you feel that a situation is about to develop in your favour. informal
2 1999 FHM She soon invited me back to her place for the other. Game on!
Farlex Partner Idioms Dictionary © Farlex 2017