A couch potato might be someone who sits long hours on their couch with a bag of potato chips in hand, but that is not where the expression comes from. As you may know, old timers often call the TV the boob tube. Someone watching the boob tube might be called a boob tuber, and a potato being the most famous of all tubers is why we say couch potato. I know…not the history you were expecting…or even wanting to hear. But I’m telling you anyway.