'securely-joined' originates from the combination of 'securely' and 'joined', where 'securely' means 'in a secure manner' and 'joined' means 'connected'.

'securely' and 'joined' have been used in English since the Middle Ages, evolving from Old French and Latin roots.

Initially, 'securely' meant 'without danger' and 'joined' meant 'united', and these meanings have largely remained the same in modern usage.