fissionableadj.

1945 H. D. Smyth Gen. Acct. Devel. Atomic Energy Mil. Purposes i. 17 Plutonium 239 is the nucleus rightly guessed to be fissionable by thermal neutrons.

1948 Times 9 Mar. 3/3 The new fissionable element is uranium of the atomic weight of 233.

1950 Amer. Speech 25 24 Reactors may be named according to fuel (uranium reactor)..addition of fissionable fuel (enriched reactor)..and so on.

1950 Amer. Speech 25 26 Fissile and fissionable..are sometimes distinguished, with fissile assigned to material that will undergo fission upon absorption of a neutron and fissionable reserved for material that fissions spontaneously.

1958 Spectator 15 Aug. 211/1 Mr. John Wardle and the Yorkshire Cricket Club continued to throw fissionable material at one another, heedless of the fall~out.

1959 Times 22 Jan. 11/2 Parties with an ideology are always more ‘fissionable’ than those without one.

1968 F. Kertesz Lang. Nucl. Sci. (Oak Ridge Nat. Lab. TM 2367) 18 Fissionable materials were shipped in containers held in a birdcage.

1946 Physical Rev. 2nd Ser. 70 108 Determining the thermal fissionability of several nuclear species.

1953 Ann. Rev. Nuclear Sci. 2 399 For convenience, this first section on the fissionability of nuclides has been divided into two parts: the first part deals with heavy elements from thorium on up, while the second part deals with medium elements from bismuth on down.