Medical Definition of SUSPENSORY LIGAMENT. : a ligament or fibrous membrane suspending an organ or part: as a: a ringlike fibrous membrane connecting the ciliary body and the lens of the eye and holding the lens in place b: falciform ligament. a ligament or fibrous membrane suspending an organ or part; especially: a ringlike fibrous membrane connecting the ciliary body and the lens of the eye and holding the lens in place — see eye illustration. ADVERTISEMENT.