Pronunciation: (plOO-tō'nē-um), [key]
—n. Chem., Physics.
a transuranic element with a fissile isotope of mass number 239 (plutonium 239) that can be produced from non-fissile uranium 238, as in a breeder reactor. Symbol: Pu; at. no.: 94.
Random House Unabridged Dictionary, Copyright © 1997, by Random House, Inc., on Infoplease.