H4XX0R

Hacker -or- To Be Hacked

This term is also classified as "L337 speak" by gamers.

Online jargon, also known as text message shorthand, used in texting, online chat, instant messaging, email, blogs, and newsgroup postings, these types of abbreviations are also referred to as chat acronyms. 

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See also : 1337  leetspeak  
NetLingo Classification: Acronyms and Text Message

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