The Tropicbirds (Phaethontidae) are three species of tropical pelagic seabirds classified in their own order. Their relationship to other living birds is unclear, and they appear to have no close relatives.

Their plumage is predominantly white, with elongated central tail feathers. The three species have a different combination of black markings on the face, back, and wings. The legs of a tropicbird are located far back on their body, making walking impossible, so that they can only move on land by pushing themselves forward with their feet.

Tropicbirds frequently catch their prey by hovering and then plunge-diving, typically only into the surface-layer of the waters. They eat mostly fish, especially flying fish, and occasionally squid.