Wordnet 3.0
NOUN (1)
1. 
 King of England from 1483 to 1485; 
 seized the throne from his nephew Edward V who was confined to the Tower of London and murdered; 
 his reign ended when he was defeated by Henry Tudor (later Henry VII) at the battle of Bosworth Field (1452-1485); 
WordNet (r) 3.0 (2006):
Richard III
    n 1: King of England from 1483 to 1485; seized the throne from
         his nephew Edward V who was confined to the Tower of London
         and murdered; his reign ended when he was defeated by Henry
         Tudor (later Henry VII) at the battle of Bosworth Field
         (1452-1485)