Slugging Sammy' is a nickname given to Hall of Fame baseball player Sammy Sosa. He was known for his power hitting and ability to hit home runs frequently. The term 'slugging' refers to the statistic of total bases divided by at bats, which measures a player's power hitting ability. Sosa was a dominant force in Major League Baseball during the 1990s and early 2000s, earning him the nickname 'Slugging Sammy'.