Dictionary.net

(Ornith.) An almost universally distributed fam. of night-flying, insectivorous birds, with enormous gape of beak ; plumage, moth-like in colouring, owl-like in texture. The British spec, Night-jar, Night-hawk, Moth-hawk, is between ten and eleven inches long. Gen. Caprimulgus, fam. Caprimulgidae [L. caprimulgus, goat-milker], ord. Picariae (Cuvier, Fissirostres, ord. Passeres).

n. A nocturnal bird of the genus Caprimulgus, something like the owl in appearance—so called from the mistaken notion that it sucks goats:—also called fern-owl, night-jar, and and night-hawk, from its cry.