ion

The word 'ion' is a direct borrowing from modern scientific Latin, which itself adopted the term from the ancient Greek word 'ἰών' (iṓn), meaning 'going'. This choice was made by the English scientist Michael Faraday in 1834, based on the suggestion of the Reverend William Whewell. Faraday needed a term to describe particles that 'go' or travel toward an electrode of opposite charge during electrolysis. Thus, the ancient Greek concept of movement was logically applied to the newly discovered electrically charged particles in motion, cementing the term in the language of physics and chemistry.

This word is a simplex form and cannot be meaningfully segmented into smaller morphemes based on its current English spelling.