Colloquial shortening of CHROMOLITHOGRAPH. (In use shortly after 1850). Also in comb.

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1868.  Daily News, 27 Nov., 5/6. The six chromo-facsimiles of my water-colour paintings … are now lying before me.

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1874.  F. Leslie’s Illust. Newspr., 10 Oct., 79 (Hoppe). Selling our new maps, pictures, chromos.

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1875.  Printing Times, 15 Jan. ‘Louis Prang,’ Mr. Prang [born 1827] was the first to apply … the designation of ‘chromos,’ being an abbreviation of ‘chromolithographs.’

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