The Collaborative International Dictionary of English v.0.48:

Copenhagen \Copenhagen\ prop. n. (Geography)
   The capital city of Denmark. Population (2000) = 1,339,395.
   [PJC]

The Collaborative International Dictionary of English v.0.48:

Copenhagen \Co`pen*ha"gen\, n. [From Copenhagen, Denmark.]
   1. A sweetened hot drink of spirit and beaten eggs.
      [Webster 1913 Suppl.]

   2. A children's game in which one player is inclosed by a
      circle of others holding a rope.
      [Webster 1913 Suppl.]

WordNet (r) 3.0 (2006):

Copenhagen
    n 1: the capital and largest city of Denmark; located on the
         island of Zealand; "Copenhagen is sometimes called the
         Paris of the North" [syn: Copenhagen, Kobenhavn,
         Danish capital]