O'B
• Fitz-James O'Brien
• Robert C. O'Brien
O'D
• Claire O'Dell
• Peter O'Donnell
• Kevin O'Donnell Jr
O'M
• Daniel O'Malley
• Kathleen O'Malley
O'N
• Ryan O'Nan
• Kathleen M. O'Neal
OBE
• Alcestis R. Oberg
ODE
• Sten Odenwald
OFF
• Andrew J. Offutt
• Jodie Offutt
OGA
• Issui Ogawa
OHL
• Ben Ohlander
OKH
• Vadim Okhotnikov
OLD
• Peter Oldale
OLI
• Chad Oliver
• Steven Guy Oliver
OLT
• Jerry Oltion
ONS
• Carl Onspaugh
ORD
• John J. Ordover
ORE
• Rebecca Ore
OSB
• Cary Osborne
OST
• Anna Oster
OUL
• The Oulipo
OVE
• A. D. Overstreet
OWE
• Mably Owen
OWO
• An Owomoyela
OYE
• Adam Oyebanji