TechnologyJuly 14, 2026

fission

/ˈfɪʃ.ən/

Definition

A nuclear reaction in which the nucleus of a heavy atom splits into smaller parts, releasing a large amount of energy.

Etymology

Derived from the Latin 'fissio,' meaning 'a cleaving or splitting.' It entered English in the 17th century to describe general splitting and was later adopted in the 20th century to describe the specific physical process of splitting atomic nuclei.

In the news

The article contrasts conventional nuclear fission with fusion, highlighting that fusion is considered safer because it avoids the long-lasting radioactive waste and risk of uncontrolled chain reactions associated with fission.

SoftBank’s Masayoshi Son sees fusion power as key to AI’s future

Read the full article ↗

The Japan Times

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