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Science & TechnologyGreekEnglish

Ion

/ˈaɪən/noun

An atom or molecule carrying an electric charge.

The Greek roots

ἰόν
ión
going, that which goes

Literally: going thing

Follow a root:ἰόν4 words

The story of the word

Faraday needed names for whatever moved through an electrolyte and wrote to William Whewell for help. Whewell sent back ion, anion and cation in 1834, all built on the Greek verb for going. The prepositions still record direction: cations travel down to the cathode, anions up to the anode.

How it travelled
Ancient Greek → scientific coinage → English
First recorded
1834

The same roots elsewhere

Other languages reached for exactly the same Greek pieces.

Same family

anioncationionosphere

In a sentence

Sodium loses an electron and becomes a positive ion.

Built on the same root

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