Gavia is a genus of birds in the family Gaviidae that includes four species of loons. Each species has its own distinct features, behaviors, and habitats. Some synonyms that are associated with gavia include diver, northern diver, great northern diver, and loon. These synonyms are used to describe the bird's characteristic diving behavior. Gavia also has various species-specific synonyms that reflect its physical traits and habitat, including black-throated diver, yellow-billed loon, Arctic loon, and Pacific loon. These synonyms help to distinguish between the different types of loons and give us a more in-depth understanding of their unique characteristics.