Any of about 60–70 species of birds (family Caprimulgidae) found almost worldwide in temperate to tropical regions. The name is sometimes applied to all birds in the order Caprimulgiformes. (The name goatsucker derives from an old belief that they sucked goat's milk at night.) Nightjars are gray, brown, or reddish brown. They eat flying insects at night. The common nightjar (Caprimulgus europaeus) has a flat head; wide, bristle-fringed mouth; large eyes; and soft plumage that results in noiseless flight. It is about 12 in. (30 cm) long. Its North American relatives include the nighthawk and whippoorwill.

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