'outlier' originates from Middle English, specifically the word 'outlyer,' where 'out-' meant 'outside' and 'lier' referred to 'one who lies or remains.'

'outlyer' transformed into the modern English word 'outlier' through the influence of the word 'lie' meaning 'to remain or stay.'

Initially, it meant 'one who lies outside,' but over time it evolved into its current meaning of 'something that is different from others in a group.'