There are several synonyms that can be used for the term "swimming season." For example, "pool season" is often used to refer to the time of year when outdoor swimming pools are open for use. "Summer swim" is another common phrase that is used to describe the period of time when people are most likely to swim in lakes, rivers, and other natural bodies of water. Other synonyms for "swimming season" might include "aquatic recreation season," "outdoor swim season," or "water sports season." Regardless of the term used, this is a time of year when many people enjoy spending time in the water and exploring all that swimming has to offer.