Dennis O'Neill may refer to:
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Dennis O'Neill (baseball)
Dennis O'Neill (November 22, 1866 – November 15, 1912) was an American Major League Baseball player. He played for the St. Louis Browns
The St. Louis Browns were a Major League Baseball team that originated in Milwaukee, Wisconsin, as the ...
(1866–1912), 19th-century baseball player
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Dennis O'Neill (manslaughter victim), British manslaughter victim
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Dennis O'Neill (rugby league), rugby league footballer of the 1970s for Great Britain, and Widnes
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Dennis O'Neill (tenor) (born 1948), Welsh tenor
See also
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Dennis O'Neil
Dennis "Denny" Joseph O'Neil (May 3, 1939 – June 11, 2020) was an American comic book writer and editor, principally for Marvel Comics and DC Comics from the 1960s through the 1990s, and Group Editor for the Batman family of titles until h ...
(born 1939; died 2020) aka Denny O'Neill, American comic book writer and editor
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Dennis Patrick O'Neil, Roman Catholic bishop
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