(n) Technocratic zealots; evangelicals of geekery. Characterized by irrational advocacy of a particular OS, console, company, or franchise.

A passionate fan of various elements of geek culture (e.g. sci-fi, comics, Star Wars, video games, anime, hobbits, Magic: the Gathering, etc.), but who lets his passion override social graces.

1. A person who is completely loyal to a game or company reguardless of if they suck or not.
2. A pathetic insult often used by fanboys themselves to try and put down people who don't like whatever it is they like.
3. See fool or SEGA.

Someone far beyond a simple fan.
No, not the tye of fan which keeps people cool.

An arrogant person who goes into an outburst every time something he likes is questioned. Fanboys usually acuse others of being fanboys. Usually use 1337 and swarm MMORPGs. Fanboys caused alot of fallouts between people when they started arguing about consoles. If you insult something that a fanboy likes, he will spam your computer up and try to insult something that you like. Most words a fanboy uses are in 1337 or end with 'X0RZ' and they spell the work 'the' as 'teh' because they think that it is 'teh ro><0|2Z!!!'
e.g. Counterstrike is teh rockxorz!

Fanboys usually use the word 'own3d' if they beat someone.
Another annoying feature of a fanboy is that if he is loyal to a console, he usually goes to rival console forums and spams the place up with inults about how his console is 'better'.
They take the 'console war' very seriously, as if it's a real war.

(Although I'm a Nintendo fan, I hate Nintendo fanboys who can't shut up because a Sony fan said that Nintendo is for kids. Dude, chill out, the console war isn't a real war!)

A person who loves something without question.

A person who has an undying urge to sway everyone that is not a believer of the belief system they have towards a game or system or every piece of hardware. If they do not succeed, they will not sway from their statement infront of anyone who knows their stancel.

Well, in the case of Urban Dictionary, it's someone who's only posted one definition, and that definition always bashes some other system.