fis·​sion·​able ˈfi-shə-nə-bəl How to pronounce fissionable (audio)
ˌfi-shə-nə-ˈbi-lə-tē How to pronounce fissionable (audio)

Examples of fissionable in a Sentence

Recent Examples on the Web In May the National Nuclear Security Administration released an investigation about four 2021 incidents: one criticality safety violation, one breach that resulted in skin contamination for three workers, and two flooding events that sent water toward fissionable materials. Sarah Scoles, Scientific American, 14 Nov. 2023 The incidents included two separate floods, a glovebox breach, and an instance in which an unsafe amount of fissionable material was placed in a dropbox. Time, 24 July 2023 Yet something was leaving Oak Ridge: Uranium 235, the fissionable isotope of the heaviest naturally occurring element on the planet. Denise Kiernan, Rolling Stone, 17 July 2023 The most important step was separating the fissionable material from the conventional high explosives that trigger the nuclear reaction. Phil Hoover, Discover Magazine, 20 Feb. 2012 The optimum would be to toss into the stream of discussion an AI outlier comment that would get everyone to go full-on fissionable red hot. Lance Eliot, Forbes, 10 July 2022 Eisenhower proposed that governments make contributions from their stockpiles of uranium and fissionable materials to an international atomic-energy agency. Rebecca Tuhus-Dubrow, The New Yorker, 19 Feb. 2021 Other fissionable atoms, Pu-239 for example, produce different suites of fission products. Andrew Karam, Popular Mechanics, 7 Jan. 2016 A criticality accident is an uncontrolled chain reaction involving a fissionable material like plutonium that releases energy and generates a deadly burst of radiation. Patrick Malone and R. Jeffrey Smith, Washington Post, 18 June 2017

These examples are programmatically compiled from various online sources to illustrate current usage of the word 'fissionable.' Any opinions expressed in the examples do not represent those of Merriam-Webster or its editors. Send us feedback about these examples.

Word History


fission entry 1 + -able

First Known Use

1945, in the meaning defined above

Time Traveler
The first known use of fissionable was in 1945

Dictionary Entries Near fissionable

Cite this Entry

“Fissionable.” Dictionary, Merriam-Webster, Accessed 25 Jun. 2024.

Kids Definition


fis·​sion·​able ˈfish-(ə-)nə-bəl How to pronounce fissionable (audio)
: capable of going through fission
fissionable material

Medical Definition


fis·​sion·​able ˈfish-(ə-)nə-bəl How to pronounce fissionable (audio) ˈfizh- How to pronounce fissionable (audio)
: capable of undergoing fission and especially atomic fission
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