Definition: "Below the hole" describes the position of a golf ball in relation to the cup, or hole, once the ball is on the green.
If the green slopes, or if the hole is cut in a position on the green that slopes, being below the hole with your approach shot or lag putt is the desired position.
Below the hole means that your ball is positioned such that you will be putting uphill to the cup. Uphill putts are generally easier than downhill putts, so below the hole us much preferable to above the hole.
Examples:
The Golf Guide positioned his ball below the hole, which leaves an uphill putt for par.
