O
| Oakes Oakley Obadiah Obed Obelius Obelix Obie O'Conner O'Connor Octavio Octavius Octavus Odell Odil Odin Odion Odo Odon Ogden Ogilvy Okan Olaf Olav Olcay Oldrich Oleg Olier Olinda Oliver Olivero Olivier Olley Ollie Olly Olney Omar Omari Omarr | Omer Oram Oran Oren Orenthal Ori Orien Orin Orion Oris Orlando Orman Ormos Oros Orran Orren Orrin Orsen Orsin Orsini Orson Orville Osborn Osborne Oscar Osgood Oskar Osman Osmar Osmen Osmond Ossian Ossie Osted Ostric Osvaldo Oswald |  Oswaldo Oswall Oswell Oswin Otello Othello Otho Otilio Otis Otto Ovid Owen Owens Owyn Oxford Oxon Oxton Oz Ozan Ozzie Ozzy |
