Mark O'Neill may refer to:
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Mark O'Neill (rugby league) (born 1975), Australian rugby league footballer of the 1990s and 2000s
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Mark A. O'Neill
Mark A. O'Neill (born 3 November 1959) is an English computational biology, computational biologist with interests in artificial intelligence, systems biology, complex systems and image analysis. He is the creator and lead programmer on a num ...
(born 1959), British entomologist and computer scientist
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Mark O'Neill (TV personality)
''Big Brother 2015'', also known as ''Big Brother 16'' and ''Big Brother: Timebomb'', was the sixteenth series of the British reality television series ''Big Brother'', hosted by Emma Willis and narrated by Marcus Bentley. The series launched on ...
(born 1984), Irish television personality and producer
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Mark O'Neill (cricketer)
Mark Dorian O'Neill (born 5 March 1959) is a former Australian cricketer who played first-class cricket from 1979 to 1991. He is the son of the former Test cricketer Norm O'Neill and athlete Gwen Wallace.
A right-handed batsman and right-arm ...
(born 1959), Australian cricketer
{{hndis, ONeill, Mark