I hear the term "over the top" a lot.
It's something a lot of players say after a bad shot, but what does it mean?
It means that the player was over the top of the backward swing line -- the downswing was outside, or over the top, of the backswing path.
A good way to picture this is to place a ball on the ground and lay a stick or another club (pointing down the fairway) behind it. The stick represents the target line -- the line you'd like the ball to fly on. Then, inches in front of your feet, place another stick or club on the ground. This stick should be parallel to the stick behind the ball.
The stick closest to your feet represents the line you'd like to send the shaft back to during your swing. When the club is waist-high, parallel to the ground, it should be inside of the stick placed at your feet.
In a good takeaway, the face of the club will be in front of your hands and not cross the stick closest to your feet.
What a lot of amateurs do during the takeaway is twist with the wrists, arms and hands brining the face of the club behind the stick on the ground. The face of the club is behind the body. This causes the downswing to be outside of the stick behind the ball.
When the downswing goes from outside-in, or "over the top," the ball slices.
One way to get rid of the slice is to improve your takeaway. Take the club away, making sure the face of the club is inside the stick closest to your feet. This will help you go from inside-out on the downswing, eliminating the slice.