Coastal environments are characterized by pronounced hydrological, physical and chemical gradients where terrestrial freshwater cycles meet the saltwater systems of the ocean. Research at this interface is inherently multidisciplinary, engaging marine chemists, biologists, geophysicists, hydrogeologists, and sedimentologists, among others. This diversity of perspectives has led to a proliferation of conceptual models and terminologies for describing coastal flow phenomena, particularly in the context of saltwater intrusion and submarine groundwater discharge. For instance, the mixing zone of saltwater and freshwater is in hydrogeology often termed ‘coastal aquifer’, in geochemistry ‘subterranean estuary’ and in biology sometimes ‘anchialine’ habitat. Similarly, the extent of the ‘coastal aquifer’ is ambiguous – does it only encompass the mixing areas or does it reach inland up to the watershed? Another example is the difference between pore water exchange and submarine groundwater discharge that is ambiguous in some instances. These issues have been the subject of ongoing debate for decades, but this initiative could be an opportunity to tackle this discussion in a structured effort. Here, we propose a comprehensive, community-driven initiative to synthesize and standardize definitions of coastal hydrological features. Our approach entails aggregating diverse datasets and conceptual frameworks in questionnaires spread to the diverse coastal research community. We will distil the information from the responses, extract features and definitions which we will then discuss in a structured way with the community. Ultimately, we will publish the product showcasing the variety of community knowledge as a community effort. We invite the conference participants to join the discussion during our poster session, shape the process and fill in the first questionnaires. Eventually, this discussion will help us to produce exchange for more compatible research between the different disciplines involved in the complex system of the coast.