'two-coloured' is a compound of English elements: 'two' and 'coloured'. 'Two' originates from Old English, specifically the word 'twā', where the root meant 'two'. 'Coloured' originates from Middle English 'coloured', from Old French 'colorer', ultimately from Latin 'color' (or 'colorare'), where the root meant 'colour' or 'to give colour'.

'two' developed from Old English 'twā' into Modern English 'two', while 'coloured' came from Latin 'color' → Old French 'colorer' → Middle English 'coloured', and the compound 'two-coloured' arose in Modern English by combining these elements.

Initially the separate elements meant 'the number two' and 'to have colour'; together they originally meant 'having two colours' and this basic meaning has remained stable into modern usage.