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.

PSO by BlackAttack(TheAfricanAssault) June 3, 2003

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

PSO by wildsidechicago August 25, 2004

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!?

PSO by Tekki January 16, 2004

PSO 

PIMP SHIT ONLY

Them niggas over there that’s PSO

PSO by Starluvvvvvv April 4, 2019

PSO 

PSO Perfect Shitting Opportunity

"The movie starts in 15 minutes this is a PSO"

PSO by FRISKEY LIL THING May 9, 2016

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.

PSO by swtcaroline December 17, 2006

PSO 

Platonic Significant Other

A best friend, life partner, whoever you spend time with. Same as S.O. but without sex or romance
NOT friendzoning, neither person wants to date and they're just best friends

My best friend is my PSO, we do everything together and people often ask if we're dating, we're for sure not though

PSO by I don't want my tits anymore September 18, 2022