Antonyms for the word "over tired" would be words that convey the opposite meaning, such as alert, energetic, invigorated, refreshed, rejuvenated, or revitalized. These words describe a state of being where one feels awake, alert, and full of energy, rather than being exhausted or fatigued. Antonyms like these can be helpful when trying to convey a positive or optimistic message, for example, when writing about a restful night's sleep, a stimulating activity, or a refreshing break from work. Using the right antonyms can make a huge difference in the tone and meaning of your writing, so it's important to choose your words carefully.