Posted on 19th November 2020 by melyn Bystyon is the Cornish word for nasty Yes, nasty in Cornish is bystyon Share this:Click to share on Twitter (Opens in new window)Click to share on Facebook (Opens in new window) Related Post navigationPrevious post: Viktori is the Cornish word for victoryNext post: Skrifwas is the Cornish word for clerk