The term 'Partridge Cousin' refers to two types of birds that are related to the partridge. The first is the PHEASANT, which is an 8-letter word. Pheasants are large, long-tailed birds that are native to Asia and Europe. They are often hunted for sport and their meat is considered a delicacy. The second is the QUAIL, which is a 5-letter word. Quails are small, ground-dwelling birds that are found in many parts of the world. They are also hunted for sport and their meat is considered a delicacy. Both the PHEASANT and the QUAIL are related to the partridge and are therefore considered partridge cousins.