PUREXMeanings1nounplutonium-uranium extraction; PUREXTechnical term in nuclear chemistry; refers to the PUREX process for reprocessing spent nuclear fuel.PUREX法ほうは使し用よう済ずみ核かく燃ねん料りょうの再さい処しょ理りに用もちいられる。The PUREX process is used for reprocessing spent nuclear fuel.