Noun
depleted uranium (uncountable)
Uranium that contains a reduced (depleted) amount of the fissile isotope U-235 compared to natural uranium; it is used in applications where the nuclear properties of the uranium are not important, and the uranium is instead being used for its mechanical or chemical properties.
Depleted uranium is preferred over similarly dense metals due to its ability to be easily machined and cast as well as its relatively low cost. Source: Internet
Depleted uranium is also used as a shielding material in some containers used to store and transport radioactive materials. Source: Internet
The DU penetrator of a 30 mm round citation Depleted uranium (DU; also referred to in the past as Q-metal, depletalloy or D-38) is uranium with a lower content of the fissile isotope U-235 than natural uranium. Source: Internet