How you feel after playing an extra long set or gig.
Some dude at a bar when you just finished your last set and are rollin up for the night-"Hey I love you guys man you really sound great! Say, I play guitar too, and I was wondering if you wanted to jam.
You - "Sorry man, I'm guitarded. Not tonight."
Normal Human: OK. I played Stairway to Heaven backwards on an actual guitar.
Guitarded One: So....?
Note: normally this is used only by the guitar player him/herself, as those in the vicinity are likely also too inebriated to notice the guitardedness.