Looks like they’re interchangeable. In a clinical setting I’ve only ever used or heard it called a pannus. We even stock “pannus retractors” (basically a sticker with Velcro on the back - sticker part slaps onto the pannus, whole thing gets pushed wherever you need it, then Velcro straps connect to that to hold it on place).

This might be a regional thing, too - chips vs fries kind of situation. Not sure where you’re posting from; I’m in that weird unstable area with all the guns that some orange neanderthal has been busy raping for the last couple of years.