Something that is so disgustingly hideous it is comparable to sin itself, not necessarily physically ugly, something so disturbingly ugly it makes your stomach churn.
1. The old renault Twingo is as ugly as sin.

2. Jesus Christ that girl is as ugly as sin.
by Arthur C September 16, 2007
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the ugliest fucking chick uve ever seen on this whole planet....so ugly it is a sin to be so hideous
"man check out that chick she is ugly as sin i thinka im gon throw up!!"
by uhhhMARISSA September 21, 2005
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a human so repulsive they are either laughable, or just generally disgusting.
"look at her, you wouldnt touch her with a bargepole, shes ugly as sin!"
by DawnHoneybees January 24, 2008
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The ugliest thing you have ever seen in your entire life.
That dress is ugly as homemade sin. She is a sweet girl and smart too, which is good because she is ugly as homemade sin.
by The Ladybug Whispers ... April 26, 2016
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A very southern phrase refering to the act of incest.

"that's as ugly as homemade sin!"
by C. Hardy October 13, 2006
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