pencilwhip Share definition Flag The act of falsifying documents for work that was in fact not really done at all. see gundecking Instead of doing the job as required, the mechanic pencilwhipped the paperwork, so his boss would think he really did the job. pencilwhip by Paul Boring September 18, 2008 0 0 Get merch Get the pencilwhip mug. Buy Now — $32.95 See more merch