atomic bomb victim
Refers to a person who suffered or died as a result of an atomic bombing, especially in the context of Hiroshima and Nagasaki.
There is a memorial monument for atomic bomb victims in Hiroshima.
被爆者 is a broader term for anyone exposed to radiation from a nuclear bomb, including survivors, while 原爆犠牲者 specifically emphasizes those who died or suffered as victims.
Compound of 原爆 (atomic bomb) + 犠牲者 (victim).