JP-4 Share definition Flag n. 1.An extremely strong cup of coffee. 2.Any powerful stimulant. Taken from the military designation for jet fuel. "Fuck Sanka! I'm mixin' up some JP-4!" JP-4 by Lionel Mandrake January 22, 2004 0 0 Get merch Get the JP-4 mug. Buy Now — $32.95 See more merch
