(as) ugly as sin

phrase

informal
: very ugly
That dog of yours is as ugly as sin.

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asudden
(as) ugly as sin
Asunción
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Cite this Entry

“(as) ugly as sin.” Merriam-Webster.com Dictionary, Merriam-Webster, https://www.merriam-webster.com/dictionary/%28as%29%20ugly%20as%20sin. Accessed 6 Mar. 2026.

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