A copyist is a skilled technician who copies the designs of a particular designer or company. Applying the technical disciplines of draping and patternmaking—and often through the means of a rub-off—couture items as well as garments worn by television and movie stars are copied and mass produced. Entire businesses have been built on the ability of the fashion copyist to successfully capture the original garment's style lines, drape, movement, and fit, together with a fabrication that is identical or appears to be identical.
Historical Dictionary of the Fashion Industry. Francesca Sterlacci and Joanne Arbuckle.