What is "radioresistance"

n. Any form of resistance that an organism has to protect itself against the harmful effects of ionizing radiation

Radioresistance is the level of ionizing radiation that organisms are able to withstand.

Ionizing-radiation-resistant organisms (IRRO) were defined as organisms for which the dose of acute ionizing radiation (IR) required to achieve 90% reduction (D10) is greater than 1000 gray (Gy)

Radioresistance is surprisingly high in many organisms, in contrast to previously held views. For example, the study of environment, animals and plants around the Chernobyl disaster area has revealed an unexpected survival of many species, despite the high radiation levels. A Brazilian study in a hill in the state of Minas Gerais which has high natural radiation levels from uranium deposits, has also shown many radioresistant insects, worms and plants. Certain extremophiles, such as the bacteria Deinococcus radiodurans and the tardigrades can withstand acute doses of ionizing radiation on the order of 5,000 Gy.