Cop"y*graph (?), n.
A contrivance for producing manifold copies of a writing or drawing.
The writing or drawing is made with aniline ink on paper, and a reverse copy transferred by pressure to a slab of gelatin softened with glycerin. A large number of transcripts can be taken while the ink is fresh.
Various names have been given to the process [the gelatin copying process], some of them acceptable and others absurd; hectograph, polygraph, copygraph, lithogram, etc.
© Webster 1913.