Fission

noun (also occasionally verb, intransitive/transitive in technical use)

/ˈfɪʃ.ən/

The splitting of a heavy atomic nucleus into two or more lighter nuclei, accompanied by the release of a large amount of energy.

✍️ Usage in a UPSC answer

India's case for an indigenous three-stage nuclear programme rests on harnessing controlled fission of its modest uranium reserves to breed plutonium, thereby converting a constrained fuel base into long-term energy security without compromising its strategic autonomy.

Synonyms

splittingcleavingdivisionseverancefragmentationpartition

Antonyms

fusionunionmergercoalescence

🌱 Word Family

fission (v), fissile (adj), fissure (n), fissionable (adj), fissility (n)

🔡 Root

Latin fissiō = a cleaving/splitting; findere = to split; -ion = process/result

📜 Etymology

From Latin fissiō ("a cleaving, splitting"), from findere ("to split").

🧠 Memory Hook

Picture a "fish" being filleted down the middle into two halves: FISH-ion = a clean split into parts. The Latin root findere ('to split') also gives us "fissure", a crack or cleft.

📝 Seen in UPSC Question Papers

Prelims 2024 — Physics
Prelims 2024 — Space Technology
Prelims 2024 — Space Technology
Prelims 2016 — Nuclear Technology
Prelims 2015 — Physics

Real UPSC previous-year questions whose text uses “Fission” — proof this word earns its place on your list.

🔬 Science & Technology 📖 Seen in: Nuclear Technology, Nanotechnology & N...

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