quadruplicate

Forms were routinely filled out in duplicate, triplicate, quadruplicate.

Since the proposed railway line was always in competition with proposals to quadruplicate the Fils Valley line, it was postponed and ultimately never built.

In 2013, a Rail Clearways project to quadruplicate the East Hills line between Kingsgrove and Revesby was completed.

A chirograph (cyrograph) is a medieval document, which has been written in duplicate, triplicate or very occasionally quadruplicate on a single piece of parchment, where the Latin word "chirographum" (or equivalent) has been written across the middle, and then cut through.