Op 

A sound one makes when something unexpected happens, or a mistake is made. It can also be referred to as a shortened version of "Oops", except it's used more casually.

Op, Drew and Eli are fighting. Is this the end of a bromance?

Op, I helped my ex cheat on his current girlfriend in a baby nursery.

Op by omgitskee November 13, 2011

OP 

1)noun.Used in the lolita community for "One "Piece,as in a dress that needs no blouse.

2)noun.Used in thae forums as "original poster,"or "Original post."

3)verb.Used in battle instances as "Overpowered."

1)"The new OP from Angelic Pretty is so cute!"

2)"Dude,read the OP."

3)"He just got OPed!

OP by Miss Lolipopp August 11, 2008

Op 

A pharse used when something akward is seen, heard or said.

Oh hell no she's not wearing that, Op!

Debby: Im going on a blind date tonight
Pat: word, tell me how it turns out.
(Debby calls Pat later that night)
Patty: How'd it go ?
Debby: Horrible
Pat: What happened
Debby: My date turned out to be Father Micheal
Pat: Op

Op by jaxjaxjaxjax February 21, 2011

op 

Online Pussy - Used on online forums

"Yo dog OP to RP conversion in the works over here"

op by Your_mom January 22, 2005

OP 

Another term for Warlock in World of Warcraft
The GM's (Game Masters) Had originally planned to call the class "OP" but decided it didn't fit with the Lore.

I just got killed by a warlock.
"I just got pwnt by an OP AGAIN!"

You just died for the infinith time to a warlock, you than decide to play one.
*DEATH by Warlock* "That's it, I'm rolling OP"

OP by Jon DDA October 3, 2007

OP 

Okay, so I've been seeing this one a lot on things like reddit no sleep and it means Original Poster.

This can be used if someone has re-posted something showing that you are referring to the person who Originally Posted whatever you're posting on.

"Then suddenly I heard something behind me..."

Commenter 1: I hope OP is okay!

Commenter 2: I hope OP updates soon if they can to tell us what was behind them!

OP by GrierUmDallas October 24, 2014

OP 

Rolland, cause he's damn OP in everything

A: Dude, that guy is so Rolland
B: Don't you mean OP?

OP by AkiAlex March 16, 2015