duotype
(ˈdjuːəʊtaɪp)
[f. duo- + type n.1]
A half-tone illustration printed from two plates made from the same monochrome negative, but etched differently to give two sets of colour-values; also, the process used to print such an illustration.
| 1913 S. H. Horgan Halftone & Photomechanical Processes 207 Duotype, two half-tone plates made from the same negative, but etched differently. 1967 Karch & Buber Offset Processes v. 176 A duotype is a two color halftone made from one halftone negative. |