Piddleton
A hybrid name to describe Prince William and Kate Middleton, just like Brangelina describes Brad Pitt and Angelina Jolie. Piddleton is generally used by people who want to take some of the starch out of the Royals.
Sister: How come William and Kate don't have an acronym like other celebrity couples?
Brother: They do. It's Piddleton.
Brother: They do. It's Piddleton.