- seabird, sea bird, seafowl - a bird that frequents coastal waters and the open ocean: gulls; pelicans; gannets; cormorants; albatrosses; petrels; etc.
--1 is a kind of aquatic bird
--1 has particulars:coastal diving bird; auk; puffin; gaviiform seabird; podicipitiform seabird; pelecaniform seabird; sphenisciform seabird; pelagic bird, oceanic bird