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2.
(On In Now)
What your girl says when she gets to impatient. Telling you to put on some protection and get the job done.
O.I.N. you bastard!
by rifraff April 17, 2003
 
3.
Oin
Explanation of surprise. Is a relation to oh.
"Man did you see that sweet ride?"

"Oin!"
by Matt249 September 04, 2008