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1) The top to a USB.

2) The head of a Ultimate Super Big penis.

3) The hat you put on a Uterus Sucking Bastard.
1) "Dude i can't find my USB cap."

2) "I can't fit your USB cap in my mouth."

3) "Hey before you go down there, you must remember to put on this hat!"
by bigsackinthemiddle April 17, 2008
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