The Nazca booby is a large seabird of the booby family, Sulidae, native to the eastern Pacific. First described by Walter Rothschild in 1902, it was long considered a subspecies of the masked booby until recognised as distinct genetically and behaviorally in 2002. It has a typical sulid body shape, with a long pointed orange-yellow bill, long neck, aerodynamic body, long slender wings and pointed tail. The adult is bright white with black and white wings, a black tail and a dark face mask.

A booby is a seabird in the genus Sula, part of the family Sulidae. Boobies are closely related to the gannets (Morus), which were formerly included in Sula.