jello Share definition Flag Mediocre sex - comes from the saying "Sex is like jello. When it's good, it's really good. But when it's bad, it's still pretty good." A: "So, you shagged her last night? How was it?" B: "Jello." A: "Beats watching TV, right?" jello by Prp Guy April 23, 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