English noun: plutonium 239 | |||
1. | plutonium 239 (substance) a highly fissionable isotope of plutonium that is used in atomic weapons and as a reactor fuel; produced by irradiating uranium 238 with slow electrons | ||
Broader (hypernym) | atomic number 94, plutonium, Pu | ||
Narrower (hyponym) | weapon-grade plutonium, weapons plutonium | ||