One year we were fishing the Canadian side of the Straights of Juan De Fuca just beyond the Swiftsure closure for halibut. We ended up catching a bunch of odd, kinda true cod looking fish that we had never caught before. One of the Game Wardens called them Sable Fish and said they were very good to eat. As I recall, they were quite buttery in flavor and a buddy also smoked some as they were a bit oily. They were excellent! I think Sable Fish are also called Black Cod!
I believe you are correct. I've heard both terms. They are tasty too. I've never fished for any of these fish, just had enough, or as much as I can when I in visit the pnw or nor cal. Salmon, and trout were have here in the Midwest/ great lakes.