a driving expression used to release your frustations at unintelligent drivers. best is used while shaking your fist.

One who either plays practical jokes on another, or who is just an annoying bitch. The word is typically used to berate a personal friend for doing something to you. I.E., if a friend shits on your chest, he or she is, by definition, a bastardcock. He or she is also fucked up. Really fucked up.