'saint' originates from Latin, specifically the word 'sanctus', where 'sanct-' meant 'holy' or 'consecrated'.

'saint' changed from Latin 'sanctus' into Old French 'seint' (or 'saint') and was borrowed into Middle English as 'seint' / 'saint', eventually becoming the modern English 'saint'.

Initially it meant 'consecrated' or 'holy (person)'; over time it retained the core idea of 'holy/virtuous person' but broadened to include general senses of exceptional goodness or patience and occasional colloquial use.