Brown Bonnet Share definition Flag The act of defacating on the head of your partner...then proceding to give them a noogie. Last night when my girlfriend was asleep, I really had to use the bathroom, but I instead gave her the Brown Bonnet. Brown Bonnet by Tom January 9, 2005 0 0 Get merch Get the Brown Bonnet mug. Buy Now — $32.95 See more merch