That is a corner cabinet. They come in any size with a front door that opens. A Lazy Susan has a turn table in it. So it realy depends if you want the one that turns or one that just has shelves.

under search type in corner cabinet and it will show you all the ones they have along with the sizes.

At the shop where I work we refer to them as corner cabinets or “susans”. That’s if you want face frame with doors. Anything else would be refereed to as corner shelf. But, that is at my shop.

After checking out Home Depot on line they referred to their cabinets as either a diagonal wall cabinet or a corner wall cabinet.