A "muscular murmur" refers to a sound that is generated by the contraction of the muscles, particularly those surrounding the heart. It can be quite challenging to find synonyms for this medical term, as it is relatively specific. However, a possible alternative could be "myocardial noise", which denotes an audible vibration produced by the muscular tissues of the heart. Additionally, "cardiac rumble" can be utilized to describe an abnormal sound produced by the heart contraction. Although these synonyms may not entirely capture the exact meaning of a muscular murmur, they provide alternative terms to describe similar medical occurrences related to heart muscle contractions.