nucleus

The story

1. Proto-Italic*knuks
2. Latinnux
3. Latinnucleu
4. English todaynucleus

Learned borrowing from Latin nucleus (“kernel, core”). The earliest uses refer to the head of a comet and the kernel of a seed, both recorded in Lexicon Technicum in 1704. The sense in atomic physics was coined by British scientist Michael Faraday in 1844 in a theoretical meaning.

Words from the same roots