reprocess

To process again.

(engineering) To extract the fissile material (mainly uranium and plutonium) remaining in spent nuclear reactor fuel, allowing it to be recycled into fresh nuclear fuel or (for plutonium and/or uranium-233 from some specialized breeder reactors) used to build nuclear weapons; may also extend to recovering nonfissile but fertile elements remaining in spent reactor fuel (such as thorium), or precious metals produced as fission products.