A game

American  

Or A-game,

noun

Informal.

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

   The candidate brought her A game to the debate.

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'A' game British  

noun

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

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Etymology

Origin of A game

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

Example Sentences

A properly trained virtual doctor will be a game changer.

From The Wall Street Journal

For brothers Boone and Ford Casady, pickleball is more than just a game, it is a passion.

From Los Angeles Times

It was also his first in 249 games for the Gunners and the first time that he has scored more than two goals in a game for a year.

From BBC

But even by the Gunners' impressive standards, scoring three in a game is a rare occurrence - this was the first time they had done so since May 2022 against Everton.

From BBC

That said, not every no-spend “challenge” is a game.

From Salon