Source : Webster's Revised Unabridged Dictionary (1913)

Vault \Vault\ (v[add]lt; see Note, below), n. [OE. voute, OF.
   voute, volte, F. vo[^u]te, LL. volta, for voluta, volutio,
   fr. L. volvere, volutum, to roll, to turn about. See
   {Voluble}, and cf. {Vault} a leap, {Volt} a turn, {Volute}.]
   1. (Arch.) An arched structure of masonry, forming a ceiling
      or canopy.

            The long-drawn aisle and fretted vault. --Gray.

   2. An arched apartment; especially, a subterranean room, use
      for storing articles, for a prison, for interment, or the
      like; a cell; a cellar. ``Charnel vaults.'' --Milton.

            The silent vaults of death.           --Sandys.

            To banish rats that haunt our vault.  --Swift.

   3. The canopy of heaven; the sky.

            That heaven's vault should crack.     --Shak.

   4. [F. volte, It. volta, originally, a turn, and the same
      word as volta an arch. See the Etymology above.] A leap or
      bound. Specifically:
      (a) (Man.) The bound or leap of a horse; a curvet.
      (b) A leap by aid of the hands, or of a pole, springboard,
          or the like.

   Note: The l in this word was formerly often suppressed in
         pronunciation.

   {Barrel}, {Cradle}, {Cylindrical}, or {Wagon}, {vault}
      (Arch.), a kind of vault having two parallel abutments,
      and the same section or profile at all points. It may be
      rampant, as over a staircase (see {Rampant vault}, under
      {Rampant}), or curved in plan, as around the apse of a
      church.

   {Coved vault}. (Arch.) See under 1st {Cove}, v. t.

   {Groined vault} (Arch.), a vault having groins, that is, one
      in which different cylindrical surfaces intersect one
      another, as distinguished from a barrel, or wagon, vault.
      

   {Rampant vault}. (Arch.) See under {Rampant}.

   {Ribbed vault} (Arch.), a vault differing from others in
      having solid ribs which bear the weight of the vaulted
      surface. True Gothic vaults are of this character.

   {Vault light}, a partly glazed plate inserted in a pavement
      or ceiling to admit light to a vault below.

Barrel \Bar"rel\ (b[a^]r"r[e^]l), v. t. [imp. & p. p. {Barreled}
   (-r[e^]ld), or {Barrelled}; p. pr. & vb. n. {Barreling}, or
   {Barrelling}.]
   To put or to pack in a barrel or barrels.

Barrel \Bar"rel\ (b[a^]r"r[e^]l), n.[OE. barel, F. baril, prob.
   fr. barre bar. Cf. {Barricade}.]
   1. A round vessel or cask, of greater length than breadth,
      and bulging in the middle, made of staves bound with
      hoops, and having flat ends or heads.

   2. The quantity which constitutes a full barrel. This varies
      for different articles and also in different places for
      the same article, being regulated by custom or by law. A
      barrel of wine is 311/2 gallons; a barrel of flour is 196
      pounds.

   3. A solid drum, or a hollow cylinder or case; as, the barrel
      of a windlass; the barrel of a watch, within which the
      spring is coiled.

Source : WordNet®

barrel
     n 1: a tube through which a bullet travels when a gun is fired
          [syn: {gun barrel}]
     2: a cylindrical container that holds liquids [syn: {cask}]
     3: a bulging cylindrical shape; hollow with flat ends [syn: {drum}]
     4: the quantity that a barrel (of any size) will hold [syn: {barrelful}]
     5: any of various units of capacity; "a barrel of beer is 31
        gallons and a barrel of oil is 42 gallons" [syn: {bbl}]
     [also: {barrelling}, {barrelled}]

barrel
     v : put in barrels
     [also: {barrelling}, {barrelled}]