fissionable

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fissionable

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From fission +‎ -able.

fissionable

1. Capable of undergoing nuclear fission; fissile.

• nonfissionable

• fissionability

fissionable (plural fissionables)

1. Any fissile or fissionable substance.
   • 1956, Bulletin of the Atomic Scientists, volume 12, number 4, page 106:

     If one nation seized the fissionables within its borders, this would “serve as a danger signal” to other nations. The wrongdoer's gain would be short-lived because other nations would take defensive action in kind.