Where does “eruginous” come from?

eruginous (English) comes from Middle French erugineux, from Latin aeruginosus, from Latin aerūgō, from Latin aes, from Proto-Italic aos, from Proto-Italic ajos, from Proto-Indo-European h₂éyos — a metal, copper, bronze.

eruginous (English): pertaining to the nature or substance of copper;...

Definitions

  1. pertaining to the nature or substance of copper;...

Ancestry of “eruginous”, step by step

StepLanguageWordMeaning
1Middle Frencherugineux—
2Latinaeruginosusrusty, covered with copper rust
3Latinaerūgōrust of copper, verdigris
4Latinaesmoney, pay, fee, fare; copper, bronze, brass;...
5Proto-Italicaosbronze, copper
6Proto-Italicajos—
7Proto-Indo-Europeanh₂éyosa metal, copper, bronze
Every word from Proto-Indo-European h₂éyos →Every word from Proto-Italic ajos →Every word from Proto-Italic aos →