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

Example Sentences

Recent Examples on the Web 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 After being sent to the weapons laboratory in Los Alamos, New Mexico, Fuchs spent his time devising a method of imploding the fissionable core of the plutonium bomb. Tony Long, WIRED, 18 Oct. 2011 See More

These example sentences are selected automatically from various online news sources to reflect current usage of the word 'fissionable.' Views expressed in the examples do not represent the opinion of Merriam-Webster or its editors. Send us feedback.

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 22 Mar. 2023.

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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