Similar to Trench feet, Trench Ass is a medical condition that is brought about by an excessive and long-term build up of moisture or faecal matter between a person's ass cheeks. Usually as a result of improper hygiene.

Common symptoms include: foul smelling cheeks, Bum Cheese, a lot of ass sweat or other liquids that may seep through clothing and onto chairs
John - "Good lord, what on Earth is that smell?!"
Bill - "Oh, that's just Gav. He got diagnosed with Trench Ass last week."
by Your_Name_Goes_Here February 16, 2019
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basically swamp ass, but with a massive wedgie
i got poo stains on my underwear because of a massive case of trench ass
by rob March 29, 2005
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