dead to the world
熟睡不醒，全然没有察觉
口语·形容熟睡不醒
英文释义
to be in a deep and sound sleep, completely unaware of one's surroundings
例句
After the long hike, he was dead to the world on the couch.
典故来源
源自比喻，指人沉睡时对外界毫无反应，如同死亡般隔绝。