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:

Vaulted \Vault"ed\, a.
   1. Arched; concave; as, a vaulted roof.
      [1913 Webster]

   2. Covered with an arch, or vault.
      [1913 Webster]

   3. (Bot.) Arched like the roof of the mouth, as the upper lip
      of many ringent flowers.
      [1913 Webster]

WordNet (r) 3.0 (2006):

vaulted
    adj 1: having a hemispherical vault or dome [syn: domed,
           vaulted]

Moby Thesaurus II by Grady Ward, 1.0:

18 Moby Thesaurus words for "vaulted":
   arched, arciform, arclike, arcual, bandy, bowed, bowlike, concave,
   convex, embowed, gibbose, gibbous, humpbacked, humped, humpy,
   hunched, hunchy, oxbow