Op. 

A term coined by Sir Nathan 'Wolfe' Leinhardt used to convey annoyance. It is pronounced as though you are starting to say a word but then abruptly stop.

I failed the History test; 'Op.'

Op. by Billy Brewer June 13, 2005

OP 

1. Overpowered
2. Original Poster: The person who begins the selected thread in that particular forum.

1. Demons are OP in this game, nerf them please!
2. The OP is wrong, what we need to do is give birds a buff instead.

OP by Jack Dos Puntos January 9, 2007

op 

Op stands for overpowered.

Comic fan 1: I love Cyborg more than the Martian Manhunter!
Comic fan 2: I agree! Martian Manhunter is too OP in my opinion and his origin doesn't work with the knowledge we have on Mars.

op by Daviddv0601 December 31, 2016

OP 

1. n. abrv. Original Poster - The original poster of a forum or imageboard thread
2. n. abrv. Original Post - The first post in a forum or imageboard thread
3. n. abrv. Opening - A common abbreviation for opening, most commonly used in Japan or regarding anime
4. n. abrv. Overpowered - Statement that something is too powerful, usually in a game

1. <someperson>The OP is stupid

2. <someperson> Sauce pl0x
<otherperson> Read the OP, the source torrent is there

3. <someperson> Anyone seen the new Haruhi OP?
<otherperson> yeah it's awesome

4. <someperson> Wow the chaingun is really op

OP by ajf.me December 1, 2010

Op 

To inform authority of an action, usually the violation of a rule, that could lead to the person who performed the action getting in trouble. Can also be used to describe a person who is prone to such behavior.

Jeremy is such an op. I tried to cheat on my test, but he opped on me.

Please don’t op, bro. Don’t be a dick.

Op by FratHouseOnFranklin October 15, 2019

op 

Op is short for the word opposition

" If you're not down for the squad you're an Op"

op by Yungboy Yogi July 6, 2017

op 

Short for Original Poster. Used on online message boards and forums.

The the message the op posted is idiotic.

op by Joe December 31, 2003