Fair middling is a commonly used phrase to describe something that is average or moderate in quality. However, there are several synonyms that can be used to convey the same meaning. Some of the commonly used synonyms for fair middling include mediocre, ordinary, passable, tolerable, adequate, and satisfactory. These words are often used to describe something that is satisfactory or acceptable, but not exceptional. They are especially useful when trying to express a lack of enthusiasm or when looking to be diplomatic in giving feedback on someone's performance. Overall, there are many words that can be used to describe something that is fair middling, and choosing the right one depends on the context and tone of the message being conveyed.