Of or pertaining in any way to muscle or muscles; composing, constituting, or consisting of muscle: as, the muscular system; muscular origin or insertion; muscular fiber or tissue.Done by or dependent upon muscle or muscles: as, muscular action; muscular movement; muscular strength.Well-muscled; having well-developed muscles; strong; sinewy; brawny: as, a muscular man.Figuratively, strong and vigorous.One of the fibers of which muscular tissue is ultimately composed.Synonyms Sinewy, stalwart, sturdy, lusty, vigorous, powerful.