# plutonium

/pɫuˈtoʊniəm/ (US) · /pluːtˈəʊniəm/ (UK) · CEFR C1 · Noun

Source: https://englishreference.com/word/plutonium
Updated: 2026-08-15

## Definition

a heavy, silver-colored metal that is radioactive and used to create nuclear energy or weapons. It does not occur much in nature and is usually made in laboratories.

For teachers: a dense, silvery-white radioactive metallic element of the actinide series, with atomic number 94. Produced primarily in nuclear reactors, it is used as a fuel in nuclear power plants and as an explosive in nuclear weapons.

## Examples

- Scientists must handle plutonium with extreme care.
- The facility was designed specifically to process and store plutonium safely away from the public.
- The discovery of plutonium in 1940 fundamentally altered the landscape of modern warfare and energy production, necessitating the development of complex international safety protocols.

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