slop Share definition Flag Oral sex of the highest caliber; known to make one's knees shake. "Man, I need some fucking slop""Cassie sucked my dick last week.Did she have that slop?Yeah, it was some slop." slop by marleyrt October 17, 2015 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