meat duff Share definition Flag A term coined by Australian sailors for a large piece of red meat (usually a full steak or several slices of roast) that are eaten as a dessert during the main meal of the day. I just had two serves of meat duff and now I am as full as a WRAN in a maneating contest. meat duff by Irish471 August 25, 2008 0 0 Get merch Get the meat duff mug. Buy Now — $32.95 See more merch