'unstructurally' originates from the prefix 'un-' meaning 'not' and the word 'structural,' which comes from the Latin 'structura,' meaning 'a fitting together, building.'

'structura' transformed into the Old French word 'structure,' and eventually became the modern English word 'structure,' with 'un-' added to form 'unstructural' and then 'unstructurally.'

Initially, it meant 'not having a structure,' and this meaning has largely remained the same in modern usage.