Having more than one home run in a single game.(adjective)
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Use "multihomer" in a sentence
"His homer total and the two multihomer games have tied World Series records — a performance so powerful that Utley has injected his name into the Series MVP discussion."
"Quentin, who had two home runs in the win on Saturday, had three multihomer games during the homestand."
"It was his 48th multihomer game and sixth this season, one short of Dave Kingman's club record set in 1976."