hit a grand slam

1. baseball To hit a home run while all three bases have runners on them. It looked like the home team was in for a sure loss, until their star batter hit a grand slam in the bottom of the ninth to tie the game. I can't believe that rookie hit a grand slam in his first major league at-bat! Don't go up there trying to hit a grand slam, just hit something to the right side of the field so the runner on third can score.

2. By extension, to achieve some kind of total or sweeping victory or success. The company has hit a grand slam with their newest product, taking the top sales spots in every major market around the world. You won't get anything done—let alone hit a grand slam—with Congress as divided as it is now. Wow, if this candidate can sweep all the swing states, she might be hit a grand slam.