The tropicbirds (family Phaethontidae) are a family of birds belonging to the monotypic order Phaethontiformes. These marine birds are generally found in the pelagic zones at tropical latitudes and closer to the shore near the tropical islands where they nest — either in holes, crevices or bare ground under bushes. They usually feed on fish on the wing, including flying fish and squids. They were traditionally known as boatswain birds after their piercing calls. All-white plumage with black markings, bright-colored bill and extremely long, thin streamers are the main features of this charismatic group of birds.

The family comprises 3 species in 1 genus, Phaethon, which is the name of the sun god Helios and the ocean nymph Clymene in Greek mythology. They are present in the pelagic zone around the Equator, in the warm waters of the Indian, Atlantic and Pacific Oceans, Red Sea and Persian Gulf.