'suitably-separated' originates from the combination of 'suitably' and 'separated', where 'suitably' means 'appropriately' and 'separated' means 'divided or kept apart'.

'suitably' and 'separated' have been used in English since the Middle Ages, and their combination into 'suitably-separated' is a modern usage to describe something that is appropriately divided.

Initially, 'suitably' and 'separated' were used independently, but their combination now emphasizes the appropriateness of the separation.