Illegal U-Turn Share definition Flag A sexual act that occurs when the man reinserts his penis into the woman's vagina, after having had it in her anus. Any doctor will tell you that nasty urinary tract infections can result from the Illegal U-Turn. Illegal U-Turn by j:vincent September 8, 2011 0 0 Get merch Get the Illegal U-Turn mug. Buy Now — $32.95 See more merch