Wordnet 3.0
NOUN (1)
1. 
 a former international labor union and radical labor movement in the United States; 
 founded in Chicago in 1905 and dedicated to the overthrow of capitalism; 
 its membership declined after World War I; 
[syn: Industrial Workers of the World, IWW, I.W.W.]
WordNet (r) 3.0 (2006):
Industrial Workers of the World
    n 1: a former international labor union and radical labor
         movement in the United States; founded in Chicago in 1905
         and dedicated to the overthrow of capitalism; its
         membership declined after World War I [syn: Industrial
         Workers of the World, IWW, I.W.W.]