grand slam • n. the winning of each of a group of major championships or matches in a particular sport in the same year, in particular in tennis or golf. ∎ Bridge the bidding and winning of all thirteen tricks. ∎ Baseball a home run hit when each of the three bases is occupied by a runner, thus scoring four runs.
"grand slam." The Oxford Pocket Dictionary of Current English. . Encyclopedia.com. (September 19, 2018). http://www.encyclopedia.com/humanities/dictionaries-thesauruses-pictures-and-press-releases/grand-slam
"grand slam." The Oxford Pocket Dictionary of Current English. . Retrieved September 19, 2018 from Encyclopedia.com: http://www.encyclopedia.com/humanities/dictionaries-thesauruses-pictures-and-press-releases/grand-slam