'robustly-formed' originates from the Latin word 'robustus,' meaning 'strong' or 'sturdy,' combined with the English word 'formed,' meaning 'shaped or constructed.'

'Robustus' transformed into the Old French word 'robuste,' and eventually became the modern English word 'robust.' The term 'formed' has been used in English since the Middle Ages.

Initially, 'robust' meant 'strong or sturdy,' and this meaning has largely remained the same in modern usage.