分ぶん裂れつ性せいぶんれつせいMeanings1nounfissionable; fissileTechnical term used in nuclear physics to describe materials capable of sustaining a fission chain reaction. Often appears in compounds like 分裂性物質 (fissile material).ウラン235は分ぶん裂れつ性せい物ぶっ質しつの一ひとつです。