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1.
Short for "Person of Sub Normal Intelligence"
<Oompa> Chouzan is a POSNI
<Chouzan> stfu, newb.
by Colin-uk August 27, 2005
 
2.
A Person of SubNormal Intelligence
Chouzan is a POSNI.
Oompa is not a POSNI.
by Oompa August 27, 2005