Wordnet 3.0
NOUN (2)
1. 
 an urban youth culture associated with rap music and the fashions of African-American residents of the inner city; 
2. 
 genre of African-American music of the 1980s and 1990s in which rhyming lyrics are chanted to a musical accompaniment; 
 several forms of rap have emerged; 
[syn: rap, rap music, hip-hop]
WordNet (r) 3.0 (2006):
hip-hop
    n 1: an urban youth culture associated with rap music and the
         fashions of African-American residents of the inner city
    2: genre of African-American music of the 1980s and 1990s in
       which rhyming lyrics are chanted to a musical accompaniment;
       several forms of rap have emerged [syn: rap, rap music,
       hip-hop]