Over-flown is a word that expresses the act of flowing or passing over something. It is often used in relation to liquid substances, such as water or alcohol. However, if we want to describe the opposite of over-flown, we can use the word "under-flown." This term refers to the act of flowing underneath or not reaching a particular point. Another suitable antonym for over-flown is simply "dry." This word indicates that there is no flow or liquid presence in a particular area. Therefore, depending on the context, the antonym of over-flown can be either under-flown or dry.