lasenfasom Share definition Flag Slang word for "Larsen Foursome". This is a foursome between a family of four. Using the family dog is optional. Are you guys watching that lasenfasom? Yeah Dave it's insane! lasenfasom by WormyKermy April 9, 2017 0 0 Get merch Get the lasenfasom mug. Buy Now — $32.95 See more merch