The Collaborative International Dictionary of English v.0.48:

Okinawa \Okinawa\ prop. n.
   1. the largest island of the central Ryukyu Islands.
      [WordNet 1.5]

   2. A campaign in the closing days of World War II in the
      Pacific (April-June 1945); in savage close-quarter
      fighting US marines and regular army troops took the
      island from the Japanese; considered the greatest victory
      of the Pacific campaign for the Americans.

   Syn: Okinawa campaign.
        [WordNet 1.5]

WordNet (r) 3.0 (2006):

Okinawa
    n 1: the largest island of the central Ryukyu Islands
    2: a campaign in the closing days of World War II in the Pacific
       (April to June 1945); in savage close-quarter fighting United
       States marines and regular army troops took the island from
       the Japanese; considered the greatest victory of the Pacific
       campaign for the Americans [syn: Okinawa, Okinawa
       campaign]