Radiated

Your character is suffering from significant amount of Radiation poisoning. The more radiation, the more deadly the effect.

More information

You could get radiated not only by being in wrong place but also for being bitten by some creature in wasteland (like Centaur. The more radiation your character recives the lower it's SPECIAL becomes. After reciving large amount of radiation your character dies.

Radiation resistance reduces amount of radiation your character is being exposed to. Rad-X can improve radiation resistance.
Radiation poisoning can be cured with RadAway or intervention of doctor in one of the cities.