One that is so wasted they have lost all sense of balance, self control and manors. This person no choice but to act like a complete ass hole. Someone that gets so drunk they piss themselves before falling through your coffee table and then puke on your couch. If a male, the goat loader lives with his parents for his entire life cycle. His parents will have caught him naked with dick in hand passed out on their couch watching paperview porn and on a bad night he will have a dried up load on his shirt or worse his chin.
Jim was such a goat loader last night, not only did he fuck my fat sister but he also shit in my refrigerator.