milf day Share definition Flag This special day happens on the 2nd Sunday in May. It usually coincides with Mother's Day. It is mostly celebrated by male teens and old, balding men. Hey dude, it's milf day today! What did you get for Patrick's mom? milf day by Jay-Zed May 9, 2008 0 0 Get merch Get the milf day mug. Buy Now — $32.95 See more merch