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3.
PSO
PSO stands for Phone Sex Operator and is a person who will engage in phone sex in exchange for money.
The PSO charged $1.99 a minute to have phone sex
by wildsidechicago August 25, 2004
 
1.
PSO
1. Short for Phantasy Star Online
2. An addicting drug that is taken through the eyes, highly addictive in large doses, smaller doses cause intrigue
I'm having PSO withdrawals, i need a fix.
 
2.
PSO
A great game avalible on DC, GC and Xbox.

I love it. Can't wait for episode 3.
PSO.. oh my god, who corrupted it!?
by Tekki January 16, 2004
 
4.
PSO
Potential Significant Other, referring to an individual not quite your significant other. Could pertain to a date, a crush, an unrequited lover, a stranger you'd like to marry, etc.
My PSO totally asked to borrow my pen in calc today.
by swtcaroline December 14, 2006
 
5.
pso
1. Short for Pelvis Shattering Orgasm - Orgasm that is so good you feel as if your pelvis will shatter.
My boyfriend was wild last night, I had 3 pso's.
by John Wright November 11, 2005