The antonyms for the word "most worn-down" can be refreshed, renewed, revitalized, rejuvenated, invigorated, energized, revitalized, restored, and revived. When something has been worn down, it means that it has been used or damaged to a great extent, losing its original quality or strength. To contrast it, these antonyms suggest the opposite state of being, where something is restored to its original state, becoming revitalized and refreshed. For instance, a tired-looking garden can be revitalized with new plants, a faded piece of cloth can be renewed with bold textile design, and a rundown building can be restored with a fresh coat of paint.