From Longman Dictionary of Contemporary Englishgrand slamˌgrand ˈslam noun [countable] 1 (also Grand Slam trademark)DS the winning of all of a set of important sports competitions in the same year Wales won the Grand Slam.2 DSBa hit in baseball which gets four points because it is a home run and there are players on all the bases3 DGCthe winning of all of the tricks possible in one game of cards, especially in bridge
Examples from the Corpus
grand slam• Martina Navratilova won four consecutive grand slam events, but not in the same year.• Capriati played aggressively from the start of her first grand slam final.• Andrews, the first leg of his grand slam.• June 26 Gwynn hits first inside-the- park grand slam in Padre history. 