What Is a 'Banana Ball' in Golf?
So "banana ball" is a slang term golfers use for a bad slice. Why? Because the curvature of a banana resembles the curvature of a slice. A slice is a golf shot in which the golf ball curves left to right for a right-handed golfer, or right-to-left for a left-handed golfer. Slices are common types of mis-hits for beginning golfers and for higher handicap golfers, although all golfers hit slices from time to time.
In a 1978 article in Golf magazine, Ernie Vossler wrote that, "There are different degrees of slice, from the touring pro's skillfully controlled fade to the hapless hacker's banana ball."
In his 1961 book, Sam Snead on Golf (affiliate link), Snead wrote of the slice:
"The slice, a 'banana ball' as compared with the deliberate left-to-right fade of the professionals, is the bane of most beginners. It can be due to having taken too wide a stance, a faulty grip, too open a stance (which means with the left foot drawn back from the line of flight), from getting the hands and body into the shot too soon or from collapsing the left arm."(Note that Snead is describing the possible causes from the perspective of a right-handed golfer. The left-right directions would be opposite for a left-handed golfer.)
You can find many tutorials on YouTube or any of the golf magazine or golf instructional websites that might help you get rid of your banana ball, if you are so afflicted.
Some golf equipment manufacturers over the years have created "anti-slice" golf clubs, designed to help minimize the slice for golfers who tend to hit one. And "banana" is sometimes in the name of those clubs, for example with the Bob Burns No Bananas driver.
Another slang term for "banana ball" is "chiquita," as in the Chiquita brand of produce, famous for its bananas.
More definitions: