What is Absorbed Dose?

Legal Definition
Absorbed dose is a physical dose quantity D representing the mean energy imparted to matter per unit mass by ionizing radiation. In the SI system of units, the unit of measure is joules per kilogram, and its special name is gray (Gy). The non-SI CGS unit rad is sometimes also used, predominantly in the USA.
-- Wikipedia
Legal Definition
The trace amounts of materials that are absorbed and retained by the body. This is measured by milligrams per kilogram of the individuals body weight per day. This is commonly called an internal dose.