Pelagic birds are a unique group of birds that inhabit the open ocean and are adapted to life on the water. While the term "pelagic bird" may be the most commonly used descriptor, there are several other words that can be used to describe these birds. One synonym could be "oceanic bird," which emphasizes their open ocean habitats. Another synonym is "seabird," which is a broader term that encompasses all birds that rely on the ocean for food and shelter. "Marine bird" is also a suitable synonym, as it emphasizes their connection to the sea. Whatever term is used, pelagic birds are fascinating creatures that have adapted to life on the open ocean in unique and remarkable ways.