"Not at issue" is a phrase often used to indicate that an aspect of a topic is not up for debate or discussion. Synonyms for this phrase include "not in question," "not up for debate," "irrelevant," "uncontested," and "not open to debate." These terms serve to clarify that the topic in question is not disputed or in need of further examination. Other possible synonyms include "settled," "resolved," "unchallenged," "foregone," and "established." Understanding the nuances between these synonyms can help writers and speakers convey their meaning with precision and clarity.