A king in the old Greek stories who tricked the gods — even cheated death itself — and was punished for it after he died. His punishment was this: push a huge rock up a hill. Every time he almost reached the top, the rock rolled back down, and he had to start again. Forever. English keeps him alive mostly through the adjective Sisyphean, which describes work that never ends and never gets anywhere: cleaning a house with small children in it, answering emails, fighting a problem that grows back as fast as you fix it. People also say "pushing the boulder up the hill" or "a Sisyphean task" without naming him at all. The feeling in the word is important. It is not just hard work — hard work can be finished. It is work that is pointless because it cannot be finished, and the person doing it knows this and keeps going anyway. The French writer Camus made the story famous again in the 1940s by arguing that we must imagine Sisyphus happy, and educated speakers sometimes reach for the name with that idea somewhere behind it. It is a bookish word; you meet it in writing more than in talk.