look up any word, like ratchet:
 
1.
Basically to have gotten fucked up.

see: merc

It comes from the word "mercenary".
Motherfucker got merc'd.
by kgst February 10, 2010
 
2.
to kill a bowel or cigarette with excessive force, usually implying a refill or replacement is really needed.
"Why aren't you smoking the bowel, Joe?"
"Because dammit Laqunada, its merc'd!"
by foxsloth August 26, 2008