wazoo
There is a respectable split among vernacularists whether "wazoo" applies to one's rump or one's porker. Ample weight for both definitions. See the delightful example below for both possible interpretations -- tuchus and ding-dong.
"How's your Father?
How's your Mother?
How's your charming sister Sue?
And, speaking of your family, how's your old Wazoo?"
How's your Mother?
How's your charming sister Sue?
And, speaking of your family, how's your old Wazoo?"
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