A fat kid with a baby looking face and a wide fat chin hanging from his neck who tries to workout and get buff but only results in him looking like a goofy looking shit. This most likely results from them gaining a small amount of muscle but still not being able to get rid of their baby fat. You'll know a duff baby when you see one.
Scott "Holy shit do you see that kid?"

Brandon "Thats a duff baby if I've ever seen one."
by Duffbabyhater696969 November 12, 2013
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