I had fully intended to use the United States Stamp Society's
A Glossary of Terms for the Collector of United States Stamps to support those who argued for
offset as the proper term. Imagine my surprise when I read the following:
Quote:
Set-off - 1) the result of ink from a newly printed sheet leaving an impression on the back of the sheet stacked on top of it; 2) the result of ink accidentally applied to the roller of a printing press being picked up by the next sheet to be printed. These freaks are sometimes misleadingly called offsets. See also Phantom Numbers.