The Collaborative International Dictionary of English v.0.48:

Vault \Vault\ (v[add]lt), v. t. [imp. & p. p. Vaulted; p. pr.
   & vb. n. Vaulting.] [OE. vouten, OF. volter, vouter, F.
   vo[^u]ter. See Vault an arch.]
   [1913 Webster]
   1. To form with a vault, or to cover with a vault; to give
      the shape of an arch to; to arch; as, to vault a roof; to
      vault a passage to a court.
      [1913 Webster]

            The shady arch that vaulted the broad green alley.
                                                  --Sir W.
                                                  Scott.
      [1913 Webster]

   2. [See Vault, v. i.] To leap over; esp., to leap over by
      aid of the hands or a pole; as, to vault a fence.
      [1913 Webster]

            I will vault credit, and affect high pleasures.
                                                  --Webster
                                                  (1623).
      [1913 Webster]

The Collaborative International Dictionary of English v.0.48:

Vaulting \Vault"ing\, n.
   1. The act of constructing vaults; a vaulted construction.
      [1913 Webster]

   2. Act of one who vaults or leaps.
      [1913 Webster]

WordNet (r) 3.0 (2006):

vaulting
    adj 1: revealing excessive self-confidence; reaching for the
           heights; "vaulting ambition" [syn: overreaching,
           vaulting]
    n 1: (architecture) a vaulted structure; "arches and vaulting"
    2: a light leap by a horse in which both hind legs leave the
       ground before the forelegs come down [syn: curvet,
       vaulting]

Moby Thesaurus II by Grady Ward, 1.0:

70 Moby Thesaurus words for "vaulting":
   aduncity, apse, aquilinity, arcade, arcature, arch, arched roof,
   arching, archway, arcuation, aspiring, bouncing, bounding, camber,
   capering, ceilinged roof, circularity, concameration, concavity,
   concha, convexity, convolution, cove, crookedness, cupola,
   curvation, curvature, curving, curvity, decurvation, decurvature,
   dome, emulous, enthusiastic, excurvation, excurvature,
   geodesic dome, hookedness, hopping, hurdle race, hurdling, igloo,
   incurvation, incurvature, incurvity, jumping, keystone, leaping,
   ogive, pole vaulting, prancing, recurvation, recurvature,
   recurvity, rondure, rotundity, saltation, sinuosity, sinuousness,
   skewback, skipping, span, springing, steeplechase, the hurdles,
   timber topping, tortuosity, tortuousness, vault, voussoir