You mean pork loin?
The first ones I had were called pork tenderloin. The ones I have now are just pork loin.
You get half or whole. I use the half for Canadian bacon.
The half is one solid piece of meat where the whole is floppy and needs to be tied up.
Half is easier to slice as well.
The half is what I called tenderloin.
Maybe they are call differently depending on where store gets their meat. Not sure.
You can Google pork tenderloin and it look just like the half loin below.