JayJay Jay A jay is a member of a number of species of medium-sized, usually colorful and noisy, passerine birds in the crow family, Corvidae. The evolutionary relationships between the jays and the magpies are rather complex. For example, the Eurasian magpie seems more closely related to the Eurasian jay than to the East Asian blue and green magpies, whereas the blue jay is not closely related to either. Systematics and species. Jays are not a monophyletic group. Anatomical and molecular evidence indicates they can be divided into an American and an Old World lineage (the latter including the ground  jays and the piapiac), while the grey jays of the genus "Perisoreus" form a group of their own. The black magpies, formerly believed to be related to jays, are classified as treepies. In culture. Slang. The word "jay" has an archaic meaning in American slang meaning a person who chatters impertinently. The term "jaywalking" was coined in 1915 to label persons crossing a busy street carelessly and becoming a traffic hazard. The term began to imply recklessness or impertinent behavior as the convention became established. In January 2014, Canadian author Robert Joseph Greene embarked on a lobbying campaign among ornithologists  in Europe and North America to get Merriam-Websters Dictionary to have a "Jabber of Jays" as an official term under bird groups. Jay A jay is a member of a number of species of medium-sized, usually colorful and noisy, passerine birds in the crow family, Corvidae. The evolutionary relationships between the jays and the magpies are rather complex. For example, the Eurasian magpie seems more closely related to the Eurasian jay than to the East Asian blue and green magpies, whereas the blue jay is not closely related to either. Systematics and species. Jays are not a monophyletic