Posted on 7th June 20177th January 2017 by melyn ‘Brilliant!’ in Cornish is ‘Splann!’ Yes, if you want to say ‘Brilliant!’ in the Cornish language, it’s ‘Splann!’. Share this:Click to share on Twitter (Opens in new window)Click to share on Facebook (Opens in new window) Related Post navigationPrevious post: Puptra is the Cornish word for everythingNext post: Seks is the Cornish word for sex