cinderella stamp

Named after Cinderella, a folk-tale underdog heroine who was treated as inferior within her family. Cinderella stamps similarly were considered inferior to postage stamps.

 

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cinderella stamp

Wikipedia

cinderella stamp (plural cinderella stamps)

1. A label resembling a postage stamp, but not issued for postal purposes by a government postal administration.

• cinderella, Cinderella