1337 speech is the act of using internet slang. Typically, 1337 speech is used by people with the IQ of a banana who think they are being cool by shaving 30 points off their IQ.

Examples,

Leik omg g3t teh lif3 l00zer!!1!
L3@rn 1337 speech l00zer
by CJWLS September 6, 2006
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