Wordnet 3.0
NOUN (2)
1. 
 a sheet or band of tough fibrous tissue connecting bones or cartilages or supporting muscles or organs; 
2. 
 any connection or unifying bond; 
The Collaborative International Dictionary of English v.0.48:
Ligament \Lig"a*ment\ (l[i^]g"[.a]*ment), n. [L. ligamentum, fr.
   ligare to bind; cf. f. ligament. Cf. Lien, n., Ligature.]
   1. Anything that ties or unites one thing or part to another;
      a bandage; a bond. --Hawthorne.
      [1913 Webster]
            Interwoven is the love of liberty with every
            ligament of your hearts.              --Washington.
      [1913 Webster]
   2. (Anat.)
      (a) A tough band or plate of dense, fibrous, connective
          tissue or fibrocartilage serving to unite bones or
          form joints.
      (b) A band of connective tissue, or a membranous fold,
          which supports or retains an organ in place; as, the
          gastrophrenic ligament, connecting the diaphragm and
          stomach.
          [1913 Webster] Ligamental
WordNet (r) 3.0 (2006):
ligament
    n 1: a sheet or band of tough fibrous tissue connecting bones or
         cartilages or supporting muscles or organs
    2: any connection or unifying bond
Moby Thesaurus II by Grady Ward, 1.0:
25 Moby Thesaurus words for "ligament":
   bone, braid, brail, cable, cartilage, cord, knot, ligation,
   ligature, line, link, nexus, ossicle, rope, spun yarn, string,
   tendon, thong, tie, twine, twist, vinculum, wire, yarn, yoke