I don't think you can make an argument the definition is settled based on popular usage when the replies to your comment show there's still plenty of contention about what it means. It hasn't entered the general lexicon yet because most people have never heard it and could only guess at what it means. Not even my students agree on what vibe coding means and they're the ones who do it most. And regardless, terms of art can still have technical meanings distinct from the general lexicon (like "theory", or the example you used "hacker", which means something different around here).