Sentence:  Shea , the <WSD>chairman</WSD> of Mayor Wagner 's Baseball Committee , will be joined on the dais by Warren Spahn , the southpaw pitching ace of the Milwaukee Braves ; Frank Graham , the Journal-American sports columnist ; Bill Mazeroski , the World Series hero of the Pittsburgh Pirates , and Casey Stengel , the former manager of the Yankees . 
Meaning of the word marked with <WSD> tags:  the officer who presides at the meetings of an organization