Definition of "returner"

Returning to school is fairly simple, but remaining there proves to be a challenge for the returners.

2002, Nilda Flores-González, School Kids/Street Kids‎, page 145

For instance, some merchants suppress the names of “serial returners”; basically, customers who repeatedly buy products that they quickly return after using them once.

2016, Robert Bly, The Marketing Dictionary for the 21st Century