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1 definition by GeneWonka

Extra innings means anal sex in accordance to the home run euphemism (where first base is kissing, second base is petting, third base is oral sex, and intercourse is a home run).
"Dude, I didn't even think I was going to get to first base with Carla, but we ended up going into extra innings!"
by GeneWonka April 22, 2007