Celebrities born in 1973
51

John O'Neill (rugby union)

player  
50

Heather O'Neill

writer  
50

Garry O'Neill

artist  
49

Fabián O'Neill

footballer  
51

Eric O'Neill

lawyer  
51

Dan O'Neill (hurler)

 
51

Alan O'Neill (footballer, born 1973)

footballer  
51

Terry a. O'Neal

writer  
51

Cassandra O'Neal

artist  
50

Pádraic Ó Neachtain

 
51

Michal Ondráček

footballer  
51

Sorin Oncică

footballer  
50

Brian O'Meara (Mullinahone hurler)

 
50

Colin O'Malley

artist  
51

Jon O'Mahony

artist  
51

Daniel O'Mahony

 
51

Paula Oliveto

lawyer  
50

Paulo César de Oliveira

 
51

José R. Oliva

politician  
50

Aleksandar Olenik

Politician  
50

Lairenjam Olen

actor  
51

Jamie Olejnik

footballer  
51

Dermot O'Leary

television  
51

Daren O'Leary

player  
51

Ciarán O'Leary

player  
50

Fatma Øktem

politician  
51

Patrik Oksanen

journalist  
51

Gašper Okorn

coach  
51

Ivan O'Konnel-Bronin

footballer  
51

Lisa O'Keefe

practitioner