Syndrome resulting from exposure to ionizing radiation (e.g., exposure to radioactive chemicals or to nuclear explosions); low doses cause diarrhea and nausea and vomiting and sometimes loss of hair; greater exposure can cause sterility and cataracts and some forms of cancer and other diseases; severe exposure can cause death within hours.
Damage to the body resulting from excessive exposure to ionizing radiation which causes symptoms like nausea, fatigue, vomiting, and diarrhea and in severe cases loss of hair, hemorrhage, inflammation and death.