The definition of hit or miss is a term used to describe something that might be good sometimes and bad others, especially when you cannot predict when it will be good or bad.(adjective)
An example of hit or miss is finding items on sale at a store you like to go to that has no predictable sale schedule. Sometimes they will be on sale and sometimes they won't be, so visiting the store is hit or miss.
See hit-or-miss in Webster's New World College Dictionary
See hit-or-miss in American Heritage Dictionary 4
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