Rad [Rad]
Rad [Rad] : A non-51 unit of absorbed energy from ionizing radiation, equivalent to the absorption of 100 ergs per gram, or 10- 2 Joule per kilogram. The corresponding 51 unit is the Gray, and 1 Gy = 100 rads. The name of this unit derives from the abbreviation for Radiation Absorbed Dose. See also: Rem