**Words that mean the opposite of "mutually exclusive" include words like "accordant," "compatible," "concordant," "congruent," "congruous," "consistent," "harmonious" and "nonconflicting."** Some phrases that mean the opposite of "mutually exclusive" include "in sync with" and "on the same wavelength."

Two things that are mutually exclusive are related to each other in such a way that each one makes the other one impossible. If two concepts are mutually exclusive, they cannot both be factual and correct at the same time. Therefore, terms that are the opposite of "mutually exclusive" must indicate that the items described can, in fact, work together in total harmony.