The Collaborative International Dictionary of English v.0.48:

Pocket \Pock"et\ (p[o^]k"[e^]t), n. [OE. poket, Prov. F. & OF.
   poquette, F. pochette, dim. fr. poque, pouque, F. poche;
   probably of Teutonic origin. See Poke a pocket, and cf.
   Poach to cook eggs, to plunder, and Pouch.]
   1. A bag or pouch; especially; a small bag inserted in a
      garment for carrying small articles, particularly money;
      hence, figuratively, money; wealth.
      [1913 Webster]

   2. One of several bags attached to a billiard table, into
      which the balls are driven.
      [1913 Webster]

   3. A large bag or sack used in packing various articles, as
      ginger, hops, cowries, etc.
      [1913 Webster]

   Note: In the wool or hop trade, the pocket contains half a
         sack, or about 168 Ibs.; but it is a variable quantity,
         the articles being sold by actual weight.
         [1913 Webster]

   4. (Arch.) A hole or space covered by a movable piece of
      board, as in a floor, boxing, partitions, or the like.
      [1913 Webster]

   5. (Mining.)
      (a) A cavity in a rock containing a nugget of gold, or
          other mineral; a small body of ore contained in such a
          cavity.
      (b) A hole containing water.
          [1913 Webster]

   6. (Nat.) A strip of canvas, sewn upon a sail so that a
      batten or a light spar can placed in the interspace.
      [1913 Webster]

   7. (Zool.) Same as Pouch.
      [1913 Webster]

   8. Any hollow place suggestive of a pocket in form or use;
      specif.:
      (a) A bin for storing coal, grain, etc.
      (b) A socket for receiving the foot of a post, stake, etc.
      (c) A bight on a lee shore.
      (d) a small cavity in the body, especially one abnormally
          filled with a fluid; as, a pocket of pus.
      (e) (Dentistry) a small space between a tooth and the
          adjoining gum, formed by an abnormal separation of the
          gum from the tooth.
          [Webster 1913 Suppl. +PJC]

   9. An isolated group or area which has properties in contrast
      to the surrounding area; as, a pocket of poverty in an
      affluent region; pockets of resistance in a conquered
      territory; a pocket of unemployment in a booming ecomony.
      [PJC]

   10. (Football) The area from which a quarterback throws a
       pass, behind the line of scrimmage, delineated by the
       defensive players of his own team who protect him from
       attacking opponents; as, he had ample time in the pocket
       to choose an open receiver.
       [PJC]

   11. (Baseball) The part of a baseball glove covering the palm
       of the wearer's hand.
       [PJC]

   12. (Bowling) the space between the head pin and one of the
       pins in the second row, considered as the optimal point
       at which to aim the bowling ball in order to get a
       strike.
       [PJC]

   Note: Pocket is often used adjectively in the sense of small,
         or in the formation of compound words usually of
         obvious signification; as, pocket knife, pocket comb,
         pocket compass, pocket edition, pocket handkerchief,
         pocket money, pocket picking, or pocket-picking, etc.
         [1913 Webster]

   deep pocket or

   deep pockets, wealth or substantial financial assets.

   Note: Used esp. in legal actions, where plaintiffs desire to
         find a defendant with "deep pockets", so as to be able
         to actually obtain the sum of damages which may be
         judged due to him. This contrasts with a
         "judgment-proof" defendant, one who has neither assets
         nor insurance, and against whom a judgment for monetary
         damages would be uncollectable and worthless.

   Out of pocket. See under Out, prep.

   Pocket borough, a borough "owned" by some person. See under
      Borough. [Eng.]

   Pocket gopher (Zool.), any one of several species of
      American rodents of the genera Geomys, and Thomomys,
      family Geomyd[ae]. They have large external cheek
      pouches, and are fossorial in their habits. they inhabit
      North America, from the Mississippi Valley west to the
      Pacific. Called also pouched gopher.

   Pocket mouse (Zool.), any species of American mice of the
      family Saccomyid[ae]. They have external cheek pouches.
      Some of them are adapted for leaping (genus Dipadomys),
      and are called kangaroo mice. They are native of the
      Southwestern United States, Mexico, etc.

   Pocket piece, a piece of money kept in the pocket and not
      spent.

   Pocket pistol, a pistol to be carried in the pocket.

   Pocket sheriff (Eng. Law), a sheriff appointed by the sole
      authority of the crown, without a nomination by the judges
      in the exchequer. --Burrill.
      [1913 Webster]

The Collaborative International Dictionary of English v.0.48:

Borough \Bor"ough\, n. [OE. burgh, burw, boru, port, town,
   burrow, AS. burh, burg; akin to Icel., Sw., & Dan. borg, OS.
   & D. burg, OHG. puruc, purc, MHG. burc, G. burg, Goth.
   ba['u]rgs; and from the root of AS. beorgan to hide, save,
   defend, G. bergen; or perh. from that of AS. beorg hill,
   mountain. [root]95. See Bury, v. t., and cf. Burrow,
   Burg, Bury, n., Burgess, Iceberg, Borrow, Harbor,
   Hauberk.]
   1. In England, an incorporated town that is not a city; also,
      a town that sends members to parliament; in Scotland, a
      body corporate, consisting of the inhabitants of a certain
      district, erected by the sovereign, with a certain
      jurisdiction; in America, an incorporated town or village,
      as in Pennsylvania and Connecticut. --Burrill. --Erskine.
      [1913 Webster]

   2. The collective body of citizens or inhabitants of a
      borough; as, the borough voted to lay a tax.
      [1913 Webster]

   Close borough, or Pocket borough, a borough having the
      right of sending a member to Parliament, whose nomination
      is in the hands of a single person.

   Rotten borough, a name given to any borough which, at the
      time of the passage of the Reform Bill of 1832, contained
      but few voters, yet retained the privilege of sending a
      member to Parliament.
      [1913 Webster]

WordNet (r) 3.0 (2006):

pocket borough
    n 1: a sparsely populated borough in which all or most of the
         land is owned by a single family