This is simply the most mackness monster on the whole entire planet. A person with this title usually has a very good erection ratio and likes penguins.
"Man that kid Lee, he is a Gila Mac.",said Lucas as Lee walked past him showing off his muscular pectorials.
You Mac is when your ice fishing and you hook a fish you fight it and it comes up to the hole and you go to grab the fish and it gets loose. Basically it's saying "Fuck you mac i'm going back down the hole"
Jack "Oh yeah i just hooked a nice laker!"
Meoff "Nice bro land that sucker"
Jack "I can see it, OOOOOOHHH!"
Jack "It's in the hole, get the gaff"
Fish "FUCK YOU MAC!"
Jack "God damn you mac"