Nickname for Great American Ballpark in Cincinnati, OH, home of the Cincinnati Reds. Used by fans of the Reds' division rival Chicago Cubs; the nickname mocks the Reds both for their futility against the Cubs (and most teams) and more specifically for the number of Cubs fans who show up at the ballpark when the Cubs are the visiting team.
The Cubbies beat the Reds 6-1 today at Wrigley South