but it is bad for one's golf score, right? i have no idea what it is, except that you should not do it!
A hook is a shot that curves to the left (for a right-handed golfer) rather than going straight. The hook results in not only an off-target shot, but also a significantly shorter shot. (insert clinton 'bent-one' joke here as desired).
I almost never hook, as I tend to slice my shots off to the right. (In fact, my golf game is usually further right than my politics.) But on those rare occasions that I hook the ball, it's a DOOZY!