Rooster Neck Flap Share definition Flag Noun: The sensitive part of the penis that dangles 2 millimetres just inferior too the penis head. 1. Wow, I would love a girl to blueberry my rooster neck flap Rooster Neck Flap by BOOMSTICK November 4, 2014 0 0 Get merch Get the Rooster Neck Flap mug. Buy Now — $32.95 See more merch