fissionable

1 of 2

adjective

fis·​sion·​able ˈfi-shə-nə-bəl  -zhə- 

ˈfish-nə-, 

ˈfizh-

: fissile sense 2

fissionability

ˌfi-shə-nə-ˈbi-lə-tē 

-zhə-;

ˌfish-nə-, 

ˌfizh-

noun

fissionability

2 of 2

noun

fis·​sion·​abil·​i·​ty ˌfish(ə)nəˈbilətē 

-lətē, 

-i also ˌfizh-

plural -es

: the property of being fissionable

—used especially of chemical elements and materials

Examples of fissionable in a Sentence

Recent Examples on the Web

Adjective

Nuclear power is heavily reliant on uranium U-235, the fissionable material used in most current nuclear facilities. — Christopher Helman, Forbes.com, 2 Apr. 2026

One goal might be to find and remove Iran’s stockpile of fissionable material. — Carl Leubsdorf, Mercury News, 14 Mar. 2026

This feature means that a relatively small amount of fissionable propellant can be used to power a missile for much longer periods of time than chemical propellants can. — Iain Boyd, The Conversation, 29 Oct. 2025

The gun-type bomb — the most basic nuclear weapon — entails using conventional explosives to fire a subcritical piece of fissionable material into another piece to then trigger the explosive nuclear reaction. — Brendan Rascius july 8, Miami Herald, 8 July 2025

There was just so much fissionable material there to generate an explosion, and that’s what happened. — Mike Fleming Jr, Deadline, 20 May 2025

These contain enriched uranium, which is high in the fissionable isotope uranium-235. — David Szondy, New Atlas, 28 Dec. 2024

Its composition varies, but for power generation, a typical mix contains slightly less than 20 percent by mass of the highly fissionable isotope uranium-235 (U-235). — IEEE Spectrum, 18 June 2024

Word History

Etymology

Adjective

fission entry 1 + -able

First Known Use

Adjective

1945, in the meaning defined above

Kids Definition

fissionable

adjective

fis·​sion·​able ˈfish-(ə-)nə-bəl 

ˈfizh-

: capable of going through fission

fissionable material

Medical Definition

fissionable

adjective

fis·​sion·​able ˈfish-(ə-)nə-bəl  ˈfizh- 

: capable of undergoing fission and especially atomic fission