The amount of radiation energy absorbed, especially by human tissue; measured in rads.
Energy imparted to matter in a suitably small element of volume by ionizing radiation divided by the mass of that element of volume. The SI unit for absorbed dose is joule per kilogram (J kg-1) and its special name is gray (Gy). ISO, 1972 RT ionizing radiation.
the amount of energy deposited in a unit of biological tissue. The units of absorbed dose are the rad and gray.