William "Bill" O'Donnell, Jr. (June 4, 1926 – October 29, 1982) was an American sportscaster.
Life and career 
A native of The Bronx, New York, O'Donnell attended Fordham Preparatory School and Fordham University. After serving in the Marines during World War II, he completed his education at Mohawk Valley Community College, then began his sportscasting career calling Syracuse Chiefs minor-league baseball and Syracuse University football and basketball.
The Baltimore Orioles hired O'Donnell in 1966, and he paired with Chuck Thompson to call their games on WJZ-TV (1966–1977), WBAL-AM (1966–1978), and WFBR-AM (1979–1981). He also contributed to national coverage of the team's appearances in the 1969 World Series on NBC Television and the 1971 World Series on NBC Radio.
In addition to the Orioles, O'Donnell called Baltimore Colts radio in 1968, and in the 1970s called regional MLB and NFL coverage for NBC and college basketball for TVS Television Network.
O'Donnell died of cancer in 1982.