When you smoke some dirt dog weed and you feel tired as fuck. Headaches are also a symptom.
"Damn, I just smoked a blunt of dirt dog, now I got a mershache"

Ronald: Hey man, i just got some if you wanna toke.

Jim: Nah man, ill pass. That shit gives me a mershache.
by Rumple Foreskin III June 15, 2010
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