ETYM Prob. jack + daw.
Common black-and-gray Eurasian bird noted for thievery; SYN. daw, Corvus monedula.
Eurasian bird Corvus monedula of the crow family. It is mainly black, but grayish on sides and back of head, and about 33 cm/1.1 ft long. It nests in tree holes or on buildings. jack daw.