positronium

American  

[poz-i-troh-nee-uhm] / ˌpɒz ɪˈtroʊ ni əm /

noun

Physics.

1. a short-lived atomic system consisting of a positron and an electron bound together.

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positronium British  

/ ˌpɒzɪˈtrəʊnɪəm /

noun

1. physics a short-lived entity consisting of a positron and an electron bound together. It decays by annihilation to produce two or three photons

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Etymology

Origin of positronium

First recorded in 1945; positron + -ium; coined by Arthur E. Ruark (1899–1979), U.S. physicist

Example Sentences

Positronium can generate huge amounts of energy.

From BBC

So what exactly is positronium?

From BBC

Discovering why there is now more matter in the Universe now than antimatter - and therefore why we exist - will take us a long way toward a new, more complete theory of how the Universe evolved, and positronium could be the key, according to Lisa Gloggler, a Phd student working on the project.

From BBC

One of the first experiments frozen positronium could be used for is to see if its antimatter part follows Einstein's Theory of General Relativity in the same way as the matter part.

From BBC

The diagram below shows why positronium is so unique.

From BBC