The antonyms for the word "most unwithered" can convey different meanings depending on the context. If we are referring to plants or flowers, the antonyms could be withered, wilted or faded. On the other hand, if we are speaking about a person's health or vitality, the antonyms could be weak, feeble, or sickly. If we are discussing an object, the antonyms could be worn, tattered, or weathered. It's important to note that the antonyms for "most unwithered" can vary depending on the situation, so it's essential to select the proper word to convey the right meaning effectively.