Skip to main content - oleum
- oligosaccharide
- Ólimbos
- Olinda
- Olisipo
- Oliva, Peace of
- Olivares, Gaspar de Guzmán, conde-duque de
- Oliver, Andrew
- Olivier, Isaac
- Olivier, Sydney Haldane Olivier, 1st Baron
- Ollivant, Alfred
- Ollivier, Émile
- Olmedo, José Joaquin
- Olmert, Ehud
- Olmütz
- Ólonos, Mount
- Olson, Floyd Bjornstjerne
- Olten
- Oltenia
- Olympias
