If someone is impulsive, it means that they act on instinct, without thinking decisions through. If you worked for an entire year to save money for a car and then suddenly decided to spend it all on an outfit instead, that would be an impulsive purchase.
Impulses are short, quick feelings, and if someone is in the habit of acting on them, they're impulsive. When stores stock chocolate at the checkout line, they are hoping you will impulsively decide to buy it. When you call the person you have a crush on after promising yourself all day to maintain an air of dignified reserve, that's impulsive behavior. We might also call impulsive behavior whimsical or capricious.
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.