Plutonium reactors are a type of nuclear reactor that utilizes plutonium as its primary fuel source. However, there are other terms or phrases that can be used as a synonym for plutonium reactors. For instance, one could refer to a plutonium reactor as a breeder reactor, as it is capable of producing more fuel than it consumes. Similarly, a fast reactor is a term that is sometimes used interchangeably with plutonium reactor, as these reactors use fast-moving neutrons to sustain the nuclear fission process. Other potential synonyms for plutonium reactors might include nuclear fission reactors or advanced reactors, as these terms encompass a broader range of reactor technologies that could include plutonium-based designs.