The Meaning of 'Water Ball' in Golf
The term "water ball" is used by golfers to refer to a golf ball they or someone else hit into the water; a cheaper or less pristine golf ball that you substitute for a better ball just before attempting to clear a body of water; or someone else's golf ball that you have retrieved from the water for your own use.
Let's take each of these in turn:
1. A ball hit into water.
This is pretty self-explanatory. You just played your golf ball right into that lake over there, which leads to a penalty. "Man, I really did not need that water ball on my score," you might say. Another golfer might say to another, "What club were you using on that water ball back on the 8th hole?" referring to a shot that golfer hit into water.
2. A cheap, used or scuffed up golf ball that you substitute for a better ball before attempting to hit over a body of water.
You have a bag full of nice, shiny new Titleists. Maybe you spent $40 on these new balls, and that's a splurge for you. Then you come to a hole that requires a tee shot over water. Boy, you sure don't want to lose one of those expensive balls you just bought, but you're not all that confident about clearing that water.
No problem, just reach into your bag and grab a "water ball." In this context, water ball means an older golf ball that's not in great shape (maybe it's scuffed or has a few nicks or you've just been playing it for weeks now); or a cheaper golf ball. In other words, this usage of water ball means a ball you're not afraid to lose in a water hazard.
Lots of recreational golfers carry a few "water balls" of this type so they don't have to risk better golf balls on shots they aren't confident of pulling off. A humorous term for this type of water ball is "AMF ball," where "AMF" sands for "adios, my friend."
3. A ball you found and fished out of the water.
Whether you carry a ball retriever or not, you've probably passed by a creek or pond or ditch or lake on a golf course, spied a golf ball under water but near the edge, and fished it out for your own possible use. Such a golf ball is another meaning of "water ball."
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