mail coif Share definition Flag A USPS-delivered hair-styling kit with instructions on how to make an idiot of yourself with an outlandish hairdo. Mail coifs are a real rip-off --- you would do better just shaving yourself bald. mail coif by QuacksO February 25, 2019 0 0 Get merch Get the mail coif mug. Buy Now — $32.95 See more merch