Wordnet 3.0
NOUN (1)
1. 
 a game played on a court with light long-handled rackets used to volley a shuttlecock over a net; 
The Collaborative International Dictionary of English v.0.48:
Badminton \Bad"min*ton\, n. [From the name of the seat of the
   Duke of Beaufort in England.]
   1. A game, similar to lawn tennis, played with shuttlecocks.
      [1913 Webster]
   2. A preparation of claret, spiced and sweetened.
      [1913 Webster]
WordNet (r) 3.0 (2006):
badminton
    n 1: a game played on a court with light long-handled rackets
         used to volley a shuttlecock over a net