Definition of Member's Bounce
You've probably had one of those rounds, playing with your best friend who also happens to be your biggest rival on the links, when it seems like every bounce of your ball is a bad one. Maybe you hit the cart path and the ball careens out of bounds; or you hit a tree and the ball richochets away from the fairway instead of into it. Or your ball just hits a small bump in the fairway and is thrown off track when it had been rolling right for the green.
And then your buddy/rival hits a tree and his ball bounces right onto the green. You just got bit by the member's bounce.
So the member's bounce is any bounce of the golf ball that is a good bounce or good break rather than a bad one.
The term derives from member-guest tournaments at private golf clubs. The idea is that the golfer in the group who is a member at the club being played knows the bumps and humps and contours of the golf course and, therefore, might just be getting some of those good bounces by design. So the original use of "member's bounce" implied some local knowledge of the beneficiary. But, really, it's just dumb luck.
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