Gylfan Share definition Flag Danish/worldwide slangterm for a very upright boy, raised on a farm in the country by a strict dad. Gylfan, for fa'en!... (in english: God damn you, Gylfan) Gylfan by Farligt Kat July 19, 2007 0 0 Get merch Get the Gylfan mug. Buy Now — $32.95 See more merch