The term "undiffused" refers to something that lacks proper distribution or is not evenly spread out. The opposite of this term is "diffused," which indicates that something is widely dispersed or spread over a broad area. Other antonyms for "undiffused" may include "spread out," "spread evenly," "disseminated," "scattered," and "broadcast." These antonyms imply that something has been evenly distributed or spread out properly. Antonyms are a great way to describe the opposite meaning of a word and can often help people to understand concepts much better.