'perilously-split' originates from the English word 'perilous,' which comes from the Old French 'perilleux,' and 'split,' from the Middle Dutch 'splitten,' meaning 'to divide.'

'perilleux' transformed into the English word 'perilous,' and 'splitten' became 'split' in modern English.

Initially, 'perilous' meant 'full of danger,' and 'split' meant 'to divide,' which together evolved into the current meaning of 'dangerously divided.'