Someone who is purposefully posting on a forum/messageboard/site sith the sole aim to irritate the regular members.

Contrary to popular belief there is much more to internet trolling than posting "OMG UR ALL SO GHEYYYY!!!1" "OMFG TRIVIUM SUX ASS U FAGS LOL" and the like. People who post such things will usually be one-post wonders and get banned, however the more experienced troll will attempt to cause some sort of havoc under the admins radar.

Common examples of trolling:
The long-term troll:
These guys don't mind waiting around for the fun to begin. They may pretend to be an average n00b, and give themselves the stereotyical interest(s) of the average member of said forum, then once having a few posts they will gradually try to spread dissent. This type may even pretend to be pally to the admin and get their msn (and try to crack their account password of course) whilst causing general disruption. May act under other proxies and slate these fake trolls on msn to the aforementioned gullible admin. These people, to be frank, usually have no life and love bringing message boards to their knees by putting considerable time into their carnage. If they crack the admins password the board is doomed.

The sophisticated troll:
This type will usually have some sort of distaste for whatever the said message board is discussing and try to cause annoyance as opposed to destructiveness. They will parody the members and see how much they can get over their heads. Subtle pisstaking being their route. They'll usually get banned in the end but will annoy an entire community using this drawn out approach.

The faker troll:
A clever troll, the main aim of the game is to, ironically, act really REALLY stupid, this trolls aim is to argue with members incoherantly, usually using text speak. This is a ploy, the troll only needs to spend 10 seconds writing the babble when the member wastes 10 minutes writing a much more wordy reply. The troll will reply with a stupid rebuff making the member post as many long replies as possible. Using the members weight against them and wasting their forum time... If they are good then their act will be believable and they probably won't get banned unless the admin is strict on txt tlk.

The rank and file spammer:
These are the first to pop into peoples minds, they are similar to the examples stated in the first paragraph. No previous experience necessary, this lot will swarm in, again, usually under proxies to maximise the destructiveness, and spam the place to hell. Only causes mild irritation if not in large numbers.

Join any popular forum for a year and I guarantee you'll see all of these.
(let's assume it's a metal board)

Faker troll (expecting to cause irritation):
"Hi im nu here u all seem kl i am rly metal rawrrr i leik slipnot and fall out boys!!!1 they r so metal! see u al on da forum xxx"

Rank and File spammer:
"LOOOOL U METAL PPL R SO GHEY WITH UR SHOUTY MUSIC WRIST SLITTING ANIMAL FUCKING SATAN SHIIIT"

by PsychoFox February 12, 2008

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1: Melkor's corruption of the Ents
2: Someone who goes out of their way to spam and flame
Troll sat alone on his seat of stone…
by Korora November 13, 2003

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Someone who deliberatly pisses people off online to get a reaction
XO iiR3AP3R OX is a right troll, all he ever does is piss us off - A lot of people
by Anonymus1996 January 01, 2015

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1. Mythical humanoid creature said to be tall and brutish, possessing great regenerative powers. they are generally thought of as evil and malevolent, and to feast on human flesh

2. A playable race from the popular MMORPG game World of Warcraft™©®(where applicable) created by Blizzard ™©® entertainment. The Darkspear Trolls are one of the proud and heroic races of the "Horde". They have the racial ability of healing themselves over time,"berserking", "Da voodoo shuffle" and bow specialization. The Horde is the opposing faction of the "Alliance"

3. An internet troll, is any group or person who creates arguments on forums, chat rooms, comment pages, or anywhere on the internet that allows open interaction between people through written text. The skilled troll can create an argument on any subject. They generally use subversive techniques to mislead people in to thinking they believe a point of view that they in fact either know to be false or do not believe at all. A cunning and clever troll can incite an argument with another person over just about an subject.

ie: troll: "Don't you ever read the bible? The earth is the center of the universe, and it's a flat disc" victim: "Wow, seriously? were you home schooled by idiots or something? One of the first things you learn in school science is that the earth is a sphere, and revolves around the sun".

A true troll never actually believes in any statement they make, they spout falsity's in order to create friction.
1. The billy goats gruff were stopped by a troll that lived under a bridge. Harry Potter, Hermoine, and Ron, encountered a troll in the girls restroom.

2. I chose a troll hunter because they have great racial ability's

3. The Landover Baptists are the worlds greatest trolls.
by Mr green April 29, 2013

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(noun) Term referring to a person who, throughout the course of a beer pong game, failed to make a single cup and as a result must sit under the beer pong table for the duration of the following game.

(Verb) In the act of defeating a person who has yet to make a cup during the current game of beer pong.
- "One more cup and you're trolled!"

- "This kid hasn't made a cup yet! He keeps this up and he's gonna end up trolled!"

-"Let's troll these kids."

- "Who's that under the table?

----"Just some kid who got trolled."

- "You serious?! I have to play with the troll??"

-"What's going on man?"
---"Just trolling some kids in pong right now."
by stamina123 February 06, 2010

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Any person who is so miserable and lacking self worth that said person makes his/her lifes goal of pissing others off and generally being a lamer.
Don't listen to that troll, he hates himself and therefore must bother everyone around him.
by Anonymous September 02, 2003

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Chiefly used in Michigan to describe the residents of Michigan's Lower Peninsula who live south of (or under) the 5 mile long Mackinac Bridge that connects Michigan's upper and lower peninsulas.
Mary's family from Houghton were concerned about their daughter marrying a Troll from Lansing.
by Jsea March 15, 2005

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Cannibalistic Ogre from mainly Scandinavian Folklore. Hairy, longnosed, brutish and Bug-eyed, they may also have multiple heads or horns. They come in all sizes, and either burst or turn to stone when sunlight hits them. They lurk in gloomy forests and dark caverns, and especially like to devour small children. However, they are usually pretty thick and can be outwitted with clever tricks.
The Females of the species are generally kinder and more intelligent, but still fairly hideous.

Gretir fought one.
Moomins are nice versions.
Gonks are sometimes called Trolls
Billy Goats Gruff are well known Troll Slayers.
To get past one guarding a bridge, just tell them someone grossly fat is waddling the same way about half a mile back. Gets em every time.
by Skeletal Munchkin February 12, 2005

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