pork flap
n.— «You have to start with the right cut of meat—pork belly. In our part of the world, we refer to it as pork flap; so when you go to get your meat to try either or both of these recipes, ask for the pork flap. Both of the recipes recommend this part of the meat but pork shoulder can work also but trust me, get the pork flap. […] 2 pounds pork belly (pork flap), sliced.» —“Tastes Like Home – Char Siu & Siew Yuk” by Cynthia Nelson Stabroek News (Georgetown, Guyana) Mar. 28, 2009. (source: Double-Tongued Dictionary)
Pork Flap this used in the north of England meaning belly pork.