Someone who hides behind a computer and threatens another person over the Internet, using very threatening language. Such a person is 110% a pussy and will run away like a deer when confronted in life but will easily trash talk on the Internet wielding his keyboard.
"Man I'll fucking cut tour throat open and feed your flesh to your mom you fucking dead man walking. Make sure the cops catch you before I do!"

"Woah we have a keyboard samurai over here. Come get me faggot!"
by The Holy Wanker February 4, 2014
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