The term 'Small, Slender Gull' can be summed up by the crossword solution of 'TERN'. Terns are a type of seabird that are characterized by their slender bodies and long wings. They are typically smaller than other types of gulls, making them easily distinguishable from other species. Terns are found in many parts of the world, including coastal areas, islands, and inland wetlands. They feed mainly on small fish, crustaceans, and insects.