This word is acceptable for play in the US & UK dictionaries that are being used in the following games:

• Lexulous
• Wordscraper
• Wordosaur

adj. superlative form of seamy: most seamy.

"Even so, the Wall Street giants have been so confident of escaping serious liability that even some of the most predatory and seamiest lenders, like Countrywide Mortgage, were quickly bought up by respectable banks like Bank of America."