The Collaborative International Dictionary of English v.0.48:

Caribbean \Car`ib*be"an\, Caribbee \Car`ib*bee\, a.
   Of or pertaining to the Caribs, to their islands (the eastern
   and southern West Indies), or to the sea (called the
   Caribbean sea) lying between those islands and Central
   America.
   [1913 Webster]

WordNet (r) 3.0 (2006):

Caribbean
    n 1: an arm of the Atlantic Ocean between North and South
         America; the origin of the Gulf stream [syn: Caribbean,
         Caribbean Sea]
    2: region including the Caribbean Islands