'securely-separated' originates from the combination of 'securely' and 'separated', where 'securely' comes from the Latin 'securus', meaning 'free from care', and 'separated' from the Latin 'separatus', meaning 'to divide'.

'securely' evolved from the Old French 'secur', and 'separated' from the Latin 'separatus', eventually forming the modern English term 'securely-separated'.

Initially, 'securely' meant 'free from care', and 'separated' meant 'to divide'. Over time, the combined term evolved to mean 'kept apart in a manner that ensures safety or security'.