'one-colored' originates from two elements: 'one' (from Old English 'ān' via Middle English 'one'), and 'color' (from Latin 'color' through Old French 'colour'), where 'ān' meant 'one' and Latin 'color' meant 'hue, covering'.

'one-colored' developed from Middle English forms such as 'one-colourèd' (also seen as 'ane-colourid') and eventually became the modern English 'one-colored' (with the alternative British spelling 'one-coloured').

Initially it meant 'having a single hue' and over time this basic meaning has remained largely unchanged as 'having only one color.'