'roundly-assembled' originates from the combination of 'roundly' and 'assembled'. 'Roundly' comes from Middle English 'roundli', meaning 'in a round manner', and 'assembled' is derived from Old French 'assembler', meaning 'to bring together'.

'Roundly' evolved from Middle English 'roundli', and 'assembled' from Old French 'assembler', eventually forming the modern English term 'roundly-assembled'.

Initially, 'roundly' meant 'in a circular manner', but over time it evolved to mean 'completely' or 'thoroughly', which is reflected in the modern usage of 'roundly-assembled'.