A game

Or A-game,

noun

Informal.

1. a person’s best effort, abilities, or achievement.

   The candidate brought her A game to the debate.

'A' game

noun

1. informal,  one's best possible performance, esp in the phrase to bring or take one's 'A' game

Word History and Origins

Origin of A game¹

In reference to a sports contest, with the letter A indicating peak performance

Example Sentences

In a weird way, I would actually like England to lose a game at some point, because what you don't want is their first loss coming in a World Cup knockout match.

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Hearts lead the defending champions by four points at the top of the Scottish Premiership, although Celtic have a game in hand.

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There was a four-point win over Bishop Montgomery in a game during which Lonzo was injured and others were sick.

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But there is a huge question about whether England would be better prepared playing a game under lights than spending time in the nets in Brisbane.

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It did not work in the fifth Test against India at The Oval, a game they should have won.

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