A dude that shows up at a large majority of metal concerts in Los Angeles. He is most often seen wearing his trademark goatskin pants, and is always drunk, or on some sort of hallucinogen. He is also reportedly "satanic".
Nobody likes .him, and he often gets kicked out of venues for starting fights, and not finishing them, as he usually gets his ass kicked/messed up in the pit
At the Korpiklaani/Tyr concert:
Me - wtf, who's that idiot with the concussion and large bump on his head?!
Trevor - That's the guy in the goatskin pants, he's always at metal concerts drunk and starting shit.
This is the definition given to people who stand in fields waiting to take pictures of trains. These people are occasionally surrounded by animals. Hence the term "Goatshagger".
This is as opposed to the standard trainspotter whom stands on the end of station platforms.
The word was first used on the Festiniog Railway in North Wales. Loads of fields and sheep. The obvious connotation has already been used so consequently, the word Goatshagger was born.