Best definition
Wrist Guitar
The act of cutting oneself.

Jeff: Dude that chick looks messed up!

Chris: Yeah man, it looks like she plays too much “wrist guitar”.
Wrist Guitar: define #2
Wrist Guitar
The act of cutting oneself intentionally.
James: Hey man check out that chick! She looks messed up!

John: Looks like she plays too much wrist guitar.