I came across the word gormless in a book, The Blade Itself, that I finished reading over the weekend. Merriam-Webster defines it as "lacking intelligence, stupid," while the OED says it means "wanting sense or discernment." In the book, the word was used to refer to a nobleman's attitude toward peasant types in a crowd. M-W gives this etymology: "alteration of English dialect gaumless, from gaum attention, understanding (from Middle English gome, from Old Norse gaum, gaumr) + -less."
M-W says gormless is a chiefly British word; that makes sense, as the writer, Joe Abercrombie, is British.