XIII is 13 in roman numerals, M is the 13th letter in the alphabet which represents Mexico or the Mexican Mafia also known as La "EME"
by Brown huero December 31, 2004
it can mean like when someone is peng or when your in a sticky situation
-xiiiii he’s so peng im gonna be his snap

or
-xiiiii your gonna get whipped when you get home
by ghazam September 4, 2019
The first Cel shaded first person shooter from Ubi soft.....its not bad
Yo download XIII demo if ya dont believe me
by Anonymous August 17, 2003
A fictional group of fictional humanoid creatures known as 'Nobodies' within the video game of Kingdom Hearts. They are beings without hearts, and have banded together in an attempt to get their hearts back. Each wear a black trenchcoat with a hood, and have a signature weapon and element. Whether they are 'evil' or not is up for debate. They lack hearts, and thus are incapable of feeling any emotions such as remorse.

Also, they are probably the only 'villains' (for lack of a better term) in history to have a bigger fanbase than the main characters. They're names are all anograms of their original names with an 'x' added.
Organization XIII is awesome.
by Gruntlord January 2, 2007
Red XIII is a god in Final Fantasy. He almost got forced to mate Aerith.
Red XIII is your god so praise him.
by Killer Lobo January 11, 2006
A group of 13 Nobodies who retained human form and are fighting to get their hearts back. They are from the popular Kingdom Hearts series. However, they are also the only villans who have a larger fan following than the main characters. Many members (such as Axel and Roxas) are paired together in yaoi relationships, canon or not. Mostly not. They were taken down member by member by Sora, the main character (who wield a giant KEY), and his many Disney and Final Fantasy friends. It is also interesting to note that Organization XIII only has one female member (Larxene) because Xion was not a true member and the rest are male.
Axel, Roxas, Demyx, and Xigbar are all Nobodies who are members of Organization XIII.
by CheshireAxel January 5, 2010