The process of plugging one nostril, and blowing air out of the other, in order to shoot out mucus. In order to make this technique successful, you must use great force, otherwise you will just look retarded when you have one nostril covered and are breathing heavily in front of your friends. But if you get that dang snot of of there...you will be known as a stud.
Jim had a nasty cold, and didn't have any tissues. He decided a farmer's blow would do lots of good, until he shot it on his girlfriend's prime rib.