Eustatism, also known as sea-level change, refers to the fluctuation of ocean water levels over time. There are several synonyms that can be used to describe this phenomenon. These include variations in sea level, fluctuations in ocean water levels, changes in sea surface, and alterations in tidal heights. Other related terms include inundation, coastal flooding, storm surges, and tsunamis, which are all also affected by changes in sea level. Understanding the synonyms for eustatism is important in studying the impact of climate change and how it affects the oceans and the coastal ecosystems. It also supports the development of mitigation and adaptation strategies for coastal communities.