The word "unquestioned" means to be unchallenged or undisputed, but there are several synonyms that one can use in place of it. One can use words like "undoubted," "certain," "unambiguous," or "indubitable" as synonyms for "unquestioned." These words convey the idea of something being firmly established and beyond doubt. Other synonyms that come to mind are "unarguable," "irrefutable," "incontestable," and "undeniable." Each of these words convey a similar sense of certainty and remove any doubt about the subject in question. In summary, when one wants to emphasize that something is not open to debate or dispute, there are several synonyms for "unquestioned" that are available for use.