When your dominant arm is more buff than your non dominant due to the effect of oftenly masturbating.
Man: "I swear, my left arm is strong, but it doesn't look like it compared to my right."
Man 2: "How often do you beat the meat? Sounds like a case of Muscle Jerkitis."
Nickname given to bales of marijuana thrown overboard or out of airplanes. Origin is reportedly from members of the US Coast Guard in the area of Southern Florida.
A sunburn or suntan focused on the left arm. It is caused by the left side of the body being the only half that gets exposed to sunlight while driving. Presumably, it would be located on the right side of the body in countries where they drive on the left side of the road.
I had a trucker's tan after driving for 10 straight hours on a sunny day.