When something is considered to be a small matter, it typically means that it is not a significant issue or problem. However, there are numerous synonyms that can replace this phrase to better convey the level of importance or triviality of the matter. Some possible alternatives include "a trifle," "a mere detail," "a minor concern," "a negligible issue," "a petty problem," "a minor inconvenience," and "a minimal challenge." Depending on the context in which the phrase is being used, these synonyms may more accurately describe the situation at hand, and help to properly communicate its level of significance.