IWW uncommon us noun 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 SynonymsIndustrial Workers of the WorldI.W.W. Related words Broader terms unionlabor movement WordNet 2.1 (Princeton University). WordNet 2.1 Copyright Princeton University. All rights reserved.