かく分裂 ぶんれつ物質 ぶっしつでしょう
kakubunretsubusshitsudeshō

Noun
Desu Copula

Expresses probability in a polite manner ("probably…") of 核分裂物質

1. Probably fissionable material.; Possibly a nuclear substance.

Polite
Presumptive
Conjecture
Physics