Charles E. Slack (February 26, 1931 – July 3, 2020) was an American college basketball player from Marshall University.

He holds the National Collegiate Athletic Association (NCAA) Division I record for the highest single-season rebound average when he grabbed 25.6 rpg in 1954–55.

[1][2] Considered one of the greatest rebounders in college basketball history,[3] he had his Marshall uniform number (#17) retired in January 2000.

[6] He was, however, an alternate for the 1960 United States men's basketball team at the Olympics.

[5] Slack was also a member of the varsity football team and was inducted into the Marshall University Athletics Hall of Fame in 1985 as a two-sport star.