What is Cod?

Cod definition and meaning on Dictionary terms:
noun, plural (especially collectively) cod, (especially referring to two or more kinds or species) cods.
any of several soft-rayed food fishes of the family Gadidae, especially Gadus morhua, of cool, North Atlantic waters.
a closely related fish, Gadus macrocephalus, of the North Pacific.
any of several unrelated fishes, as rockfishes of the genus Sebastes.