One's legs and feet, used for walking; travel by foot. Also "shanks' nag." A reference to the shank— the lower leg between the knee and the ankle—and the use of ponies or horses for travel. My bicycle fell apart three miles away from home, so I had to use shank's nag to go the rest of the way.Unfortunately, with the sedentary lifestyle many lead today, shank's nag has largely become an obsolete mode of travel.