I'd guess some kind of farm tool -- either part of a piece of machinery, or possibly something that had a long handle (like the size of a rake handle). It seems somewhat familiar, but I can't place it. IMO the tang is at the wrong angle for it to have been a hand-held knife.
We have some called corn knives, but they were a bit thinner and without the “hook” at the end. Assuming there may have been different variants. Guessing it’s some sort of reaping instrument/small scythe.
I personally think it's a homemade bushcraft knife after a ton of comparisons with all kinds of tools. Anyone know an age range? It does have a lot of rust layers . I still don't have all the layers off yet