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Science & TechnologyGreekEnglish

Baryon

/ˈbæriɒn/noun

A subatomic particle made of three quarks, such as a proton or neutron.

The Greek roots

βαρύς
barús
heavy

Literally: heavy one

Follow a root:βαρύς5 words

The story of the word

Abraham Pais proposed the name in 1953, sorting particles by mass: baryons heavy, mesons middling, leptons light. Mass turned out to be the wrong criterion, and the modern definition counts quarks instead, but the names stuck. Cosmologists still speak of baryonic matter, meaning the ordinary stuff that stars and people are made of, roughly five per cent of the universe.

How it travelled
Ancient Greek → scientific coinage → English
First recorded
1953

Same family

barometerbaritoneisobarbarometric

In a sentence

Only about five per cent of the universe is baryonic matter.

Why there is more matter than antimatter is called the baryon asymmetry problem.

Built on the same root

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