'nonpigmented' originates from English, formed by the negative prefix 'non-' (from Latin 'non', meaning 'not') plus the adjective 'pigmented', which derives from Latin 'pigmentum' meaning 'coloring matter'.

'pigmented' comes from the noun 'pigment' (from Latin 'pigmentum'), which passed into English via Old French 'pigment'; in modern English the negative prefix 'non-' was attached to create 'nonpigmented'.

Initially 'pigmentum' meant 'a coloring substance'; over time 'pigment' kept the sense of a substance that gives color, and 'nonpigmented' has come to mean 'not having such pigment', a usage retained in modern technical and medical contexts.