Bill Hassamaer
- Given Name
- William Louis
- Nickname(s)
- Roaring Bill
- Born
- 7/26/1864 — St. Louis, MO, USA
- Died
- 5/25/1910 — St. Louis, MO, USA
- Weight
- 180 lbs
- Height
- 6' 0"
- Team(s)
- Washington Senators (1894–1895)Louisville Colonels (1895–1896)
- Debut
- 1894-04-19
- Final Game
- 1896-07-06
- Gravesite
- Find-a-Grave