'aerugo' originates from Latin, specifically the word 'aerūgō,' where 'aer-' meant 'copper' and '-ūgō' referred to 'rust or verdigris.'

'aerūgō' was used in Latin to describe the green rust on copper, and it eventually became the modern English word 'aerugo.'

Initially, it meant 'green rust on copper,' and this meaning has largely remained the same in modern usage.