Nuclear material composed of atoms that readily absorb neutrons and decay into other elements, producing fissionable materials. One such element is uranium-238, which decays into plutonium-239 after it absorbs a neutron. Fertile material alone cannot sustain a fission chain reaction.
In nuclear technology, a term describing a substance that is not capable of sustaining a chain reaction, but which can be converted into a fissionable material in a nuclear reactor.
Material that is not fissile, but which can be converted into a fissile material. Uranium-238 and thorium-232 are the principal fertile materials.