#op- is a prefix indicating that the word it is attached to is the target of a hacktivist attack by an individual or group under the mantle of "Anonymous." The word it is attached to could also be the entity avenged by the hacker attacks.
Anonymous A: "Now Ireland's talking about legalizing web censorship?"
Anonymous B: "That's why #Op- Ireland (#OpIreland) is in full force. We've already hacked some of their government websites.
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Anonymous C: "Why can't I get my files from MegaUpload anymore?"
Anonymous D: "Dude, have you had your head in the cloud. Don't you know the feds took down the site?"
Anonymous C: "Man,*&%$ that! #OpMegaUpload! See how the feds like their own medicine.
Anonymous B: "That's why #Op- Ireland (#OpIreland) is in full force. We've already hacked some of their government websites.
_______________________________________
Anonymous C: "Why can't I get my files from MegaUpload anymore?"
Anonymous D: "Dude, have you had your head in the cloud. Don't you know the feds took down the site?"
Anonymous C: "Man,*&%$ that! #OpMegaUpload! See how the feds like their own medicine.
by Ghaliji February 20, 2012

Opening Post. The first post in a topic on an online discussion board, with which the topic is "opened".
by Mr. British July 17, 2006

by KitkatThatsHot July 12, 2016

Aside from meaning Original Poster, "op" can also simply mean "oh" or can be a statement typed after something peculiar has happened, or something that leaves you speechless.
This meaning has been made popular by Tumblr.
This meaning has been made popular by Tumblr.
by teenmother October 27, 2011

by ๐๐๐๐ April 2, 2019

by andreasuckstitties June 13, 2018
