資料來源 : Webster's Revised Unabridged Dictionary (1913)

Rotten \Rot"ten\, a. [Icel. rotinn; akin to Sw. rutten, Dan.
   radden. See {Rot}.]
   Having rotted; putrid; decayed; as, a rotten apple; rotten
   meat. Hence:
   (a) Offensive to the smell; fetid; disgusting.

             You common cry of curs! whose breath I hate As reek
             of the rotten fens.                  --Shak.
   (b) Not firm or trusty; unsound; defective; treacherous;
       unsafe; as, a rotten plank, bone, stone. ``The deepness
       of the rotten way.'' --Knolles.

   {Rotten borough}. See under {Borough}.

   {Rotten stone} (Min.), a soft stone, called also {Tripoli}
      (from the country from which it was formerly brought),
      used in all sorts of finer grinding and polishing in the
      arts, and for cleaning metallic substances. The name is
      also given to other friable siliceous stones applied to
      like uses.

   Syn: Putrefied; decayed; carious; defective; unsound;
        corrupt; deceitful; treacherous. -- {Rot"ten*ly}, adv.
        -- {Rot"ten*ness}, n.

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.

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

   {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.

資料來源 : WordNet®

rotten borough
     n : an English parliamentary constituency with few electors