The phrase "zonk out" typically refers to falling asleep or becoming unconscious due to tiredness, boredom, or the effects of drugs or alcohol. Some antonyms for this expression include waking up, becoming alert, being attentive, maintaining focus, and staying awake. Depending on the context, alternatives such as paying attention, concentrating, being productive, staying active, and remaining vigilant can also convey the opposite of zonking out. Whether you're trying to shake off a drowsy feeling, stay attentive during an important meeting, or simply avoid nodding off in a boring class, incorporating these antonyms into your vocabulary can help you communicate your thoughts and feelings more accurately.