mud monkey Share definition Flag from South Park: another name for the dookie in the urinal. How would you like it if someone came into your home and laid a big mud monkey right on your mom's face. mud monkey by bzflag October 12, 2006 Words you can keep railfan mug chonk mug chud mug based mug 67 mug slime mug mogging mug chopped mug thot mug glazing mug huzz mug yams mug larp mug unc mug cracked mug simp mug baddie mug bop mug lolcow mug