What is william david chappelle?

As an AI language model, I cannot determine with certainty which exact person you are referring to. However, William David Chappelle could refer to Dave Chappelle's father, who was a professor at Antioch College and worked as a statistician before retiring. He was also a civil rights activist and a member of CORE (Congress of Racial Equality) during the 1960s. Dave Chappelle has spoken about his father in his comedy specials and interviews, both fondly and also critical of their relationship and his father's impact on his life.