Waked up is an expression used to describe the action of waking up from sleep. However, there are a few antonyms that can be used to describe the opposite of waking up. One such antonym is "fall asleep," which means to go to sleep or become unconscious. Another antonym that can be used is "slumbering," which refers to the state of being in a light sleep or dozing off. Other antonyms include "catnap," "doze," and "snooze," which all describe different forms of sleeping. While waking up is considered a positive experience for most of us, these antonyms can be used in various contexts to describe different states of rest or sleep.