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Added 9 October 2026

fission

/ˈfɪʃən/ noun

Latin root: fissiōnem Wiktionary

noun Definition from WordNet 3.1, Princeton University. Pronunciation from Wiktionary, via Kaikki.org. More about fission at Wordnik → Where our words come from →

Reproduction of some unicellular organisms by division of the cell into two more or less equal parts.
A nuclear reaction in which a massive nucleus splits into smaller nuclei with the simultaneous release of energy.

Origin

Borrowed from Latin fissiōnem, accusative singular of fissiō (“the act of breaking up”), from findō (“split, divide”).

From Wiktionary, via Kaikki.org (CC BY-SA)

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