fuckbutter Share definition Flag A derogotory term used for any type of natural lubrication produced during the act of sex. Used as a vulgar exclamation. "Aw, fuckbutter! My cock got caught in the belt sander." fuckbutter by pookie August 30, 2003 0 0 Get merch Get the fuckbutter mug. Buy Now — $32.95 See more merch