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1.
An opinion concerning another's mental wellness.
"That fucker's crazier than a shithouse rat."
by Modge September 21, 2003
 
2.
It doesn't get any worse then this!
That bitch is as fucked as a Shit House Rat
by Phat Boys April 02, 2004
 
3.
Something or someone that would live in a port-a-potty or an outhouse,Freaky,Gross
That bitch is uglier than a shit house rat
Shes crazier than a shit house rat
by hardrider93 July 22, 2009