'sideline' originates from English, specifically the word 'side' and 'line', where 'side' meant 'the edge' and 'line' meant 'a mark or boundary'.

'sideline' changed from the English word 'sideline' and eventually became the modern English word 'sideline'.

Initially, it meant 'the boundary line of a field', but over time it evolved into its current meaning of 'to remove from active participation'.