William P. Murphy, American physician and academic, Nobel Prize laureate (died 1987)

William Parry Murphy Sr. was an American physician who shared the Nobel Prize in Physiology or Medicine in 1934 with George Richards Minot and George Hoyt Whipple for their combined work in devising and treating macrocytic anemia.

The Nobel Prize in Physiology or Medicine is awarded yearly by the Nobel Assembly at the Karolinska Institute for outstanding discoveries in physiology or medicine. The Nobel Prize is not a single prize, but five separate prizes that, according to Alfred Nobel's 1895 will, are awarded "to those who, during the preceding year, have conferred the greatest benefit to humankind". Nobel Prizes are awarded in the fields of Physics, Medicine or Physiology, Chemistry, Literature, and Peace.