A minor or incidental game within a larger video game.(noun)
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Use "minigame" in a sentence
"A new mic minigame has also been added to garner you a little extra cash, but the amount is so small that the minigame is a moot effort."
"After the party defeated Nue, we gained access to the fishing minigame which is a sidequest you can continue to make use of for the whole duration of the game, with gradually progressing quality of the items available with its help."
"Before the term "minigame" became a four-letter word, it used to be a pleasant surprise to have a separate, simple game within the confines of another."