Posted on 22nd May 2016 by melyn Surneth is the Cornish word for certainty Yes, certainty in Cornish is surneth Share this:Click to share on Twitter (Opens in new window)Click to share on Facebook (Opens in new window) Related Post navigationPrevious post: Koriander is the Cornish word for corianderNext post: Pockya is the Cornish word for thrust