If something is extremely tight, then it could be said to be 'tighter than a gnat's chuff.'
"So there I was yeah, just pulled this crackin' bird yeah, took her upstairs, took her mini off, and whoa! She was tighter than a gnat's chuff!"
"Colin, please don't talk like that at the dinnertable."
by Bonny lad November 11, 2004
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